# Mini ITX PC running Windows 10 Pro -noise issue



## garysummers (Oct 25, 2010)

Currently building a PC to be installed in the trunk and will provide the audio sources for a 5.1 audio system,
Have everything set up in my living room for testing before install.
My issue is a very low level noise that appears to coincide with activity on the hard drive.
Equipment:
Asrock Z390-ITX/AC Mobo
Intel Core I7-9700 3.6GHZ 8 Core processor
Crucial Ballistix 16 GB DDR4-3000 CL 15 RAM
Samsung 970 EVO PLUS 500 GBM.2-2280 SSD
Crucial Ballistix 2 TB 2.5" SSD
Noctua NH-L9I 33.84 CFM CPU Cooler
(2) Noctua F12 PWM 54.97 CFM 120mm Fans
EVGA/NU AUDIO 7.1 32bit/258Khz Sound Card
Mini Box M4-ATX-250 PSU
All installed in a SligerSM560 Case

The noise is present no matter where the volume on the PC is set.
I am also running two MiniDSP CDSP 8X12's which even when both are muted and the volume on the computer is turned off the noise is still present. Again the noise never gets louder or quieter. When music is playing it is inaudible. Just the purist in me wants it gone!!
It definitely corresponds with activity on the computer. When graphics come up on screen it is the worst.
Has anyone dealt with this kind of issue. My searches on the web have come up with several reasons but the solutions have not worked. Ground is the most common response. I have all components grounded to the same ground block,
Appreciate any help!


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## garysummers (Oct 25, 2010)

Tried to edit my previous post but can't. Guess that went away with the improved DIYMA!
I need to add that the noise is also activated by mouse and keyboard activity.


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## Ge0 (Jul 23, 2007)

Try using optical out to a multichannel external audio interface vs. a sound card that grabs data and power from a noisy computer bus?


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## garysummers (Oct 25, 2010)

Ge0 said:


> Try using optical out to a multichannel external audio interface vs. a sound card that grabs data and power from a noisy computer bus?


Optical does not have the bandwidth to play 6 channels at full resolution. I have been down the Dolby Digital and DTS routes and the audio quality is not acceptable.
With the sound card I can play 6 channels of audio at 24bit/192Khz. Yes, I have many 5.1 recordings at that resolution. The card is actually processing at 32bit. 
Again the noise is not audible when sound is played. Not audible in the midrange or tweeter. Just the mid basses. It's in that frequency range. 
According to EVGA the sound card is shielded. It is powered off a the M4-ATX power supply SATA buss. 
Just one of those annoying bugs that I would love to solve before install. 
Appreciate the reply!!


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## Ge0 (Jul 23, 2007)

garysummers said:


> Optical does not have the bandwidth to play 6 channels at full resolution. I have been down the Dolby Digital and DTS routes and the audio quality is not acceptable.
> With the sound card I can play 6 channels of audio at 24bit/192Khz. Yes, I have many 5.1 recordings at that resolution. The card is actually processing at 32bit.
> Again the noise is not audible when sound is played. Not audible in the midrange or tweeter. Just the mid basses. It's in that frequency range.
> According to EVGA the sound card is shielded. It is powered off a the M4-ATX power supply SATA buss.
> ...


You forgot to include the nugget about noise only affecting midbass. You also did not make mention about the resolution of your 5.1 channel recordings.

Have you tried contacting EVGA about this issue?


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## lithium (Oct 29, 2008)

Random suggestion, ground the minidsp chassis to ground. I've found a post or two where it helps for some reason. I haven't tried on my 6x8 yet so who knows how or why it worked for those guys.


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## garysummers (Oct 25, 2010)

Ge0 said:


> You forgot to include the nugget about noise only affecting midbass. You also did not make mention about the resolution of your 5.1 channel recordings.
> 
> Have you tried contacting EVGA about this issue?


Sorry for my omissions, not intentional!
In my experience thus far with EVGA is that I know more about their sound card than they do. I talked to a Tech support guy there about another issue and it was clear he was in the dark.
They make great graphics cards and I bet he knew a lot about that. He just kept telling me to return the card through Amazon. The only reason they developed a sound card was because the CEO of the company is a devout audiophile. I figured the issue out myself.


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## garysummers (Oct 25, 2010)

lithium said:


> Random suggestion, ground the minidsp chassis to ground. I've found a post or two where it helps for some reason. I haven't tried on my 6x8 yet so who knows how or why it worked for those guys.


Worth a try! Thanks for the reply.


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## Ge0 (Jul 23, 2007)

garysummers said:


> Sorry for my omissions, not intentional!
> In my experience thus far with EVGA is that I know more about their sound card than they do. I talked to a Tech support guy there about another issue and it was clear he was in the dark.
> They make great graphics cards and I bet he knew a lot about that. He just kept telling me to return the card through Amazon. The only reason they developed a sound card was because the CEO of the company is a devout audiophile. I figured the issue out myself.


My whole reason behind asking if you tried asking EVGA. I know their CEO drove the development of this sound card and really cares about audio quality. But, it appears help from the minions in basic customer support is futile.

Crosstalk is occurring somewhere in the system. Unfortunately this could be a number of things in such a system. This includes the motherboard and any external connected components.

I see lithium recommended a fix. It's easy enough. Try it out.


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## garysummers (Oct 25, 2010)

Ge0 said:


> My whole reason behind asking if you tried asking EVGA. I know their CEO drove the development of this sound card and really cares about audio quality. But, it appears help from the minions in basic customer support is futile.
> 
> Crosstalk is occurring somewhere in the system. Unfortunately this could be a number of things in such a system. This includes the motherboard and any external connected components.
> 
> I see lithium recommended a fix. It's easy enough. Try it out.


Once I heard this sound card and I was listening to several other options, I upgraded to another case to have two PCIe slots, which this card requires. Not easy to find in the miniITX form factor.
I was auditioning the sound cards through my home McIntosh 5.1 system. Playing hi-resolution discreet 5.1 sound files up to 24/192khz on all 6 channels.
The sound stage that was produced by this card was amazing. Bass and mid bass definition excellent. Very natural mid and hi end. You also have the option of changing op-amps. Have not gone there yet. Well worth the $300. I see a lot of returns on Amazon so QC of the product may by suspect. I have a back-up. You can engineer the greatest product in the world but if you can't build it to last and have service people with knowledge of the product, that's not good. I am hoping for the best!

I tried grounding the Mini DSP chassis. No change.
Thanks again!


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## Ge0 (Jul 23, 2007)

You could look into external audio interfaces. But, I fear your ability to pass HiRes multi-channel audio would go away. That is unless you could do the decoding upstream and then pass it on.

I just bought a Focusrite Scarlett 18i20 for another purpose. If you had something upstream that could decode the audio and then send to the stream to a device like mine you would be golden.


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## CrimsonCountry (Mar 11, 2012)

I was going to suggest moving the card outboard with a PCIe extension (even though though its shielded, still could be less noisy) but it may very well be an issue with the card itself given that it's only affecting certain channels.

I will say nearly every audio card I looked at measured very well in the 2 main channels out but significantly worse for the other outs. Most seem to be using the advertised, high-bit-rate DACS for headphone use only and used lesser DACS for the others. Also, with the M4-ATX, I've read reports of it causing interference itself unless it was isolated. So it could be a lot of things to troubleshoot.

I spent a lot of time researching options for my PC setup as well and decided to move the sound off the board into a DAC or pro audio device like Geo mentioned. I ended up finding a used MiniDSP UDAC8 which allows me avoid noise issues within my case given it's a USB DAC. I do all my EQ work/channel routing via Jriver. It accepts up to 24/192 and does 5.1 as well. I will say the DAC didn't measure the best over on AudioScience for signal to noise, but it was right up there with the RSX-GS9...which seems to fair well enough here.

I hope you get it fixed with your card though. At least there are few relatively cheap options to process multichannel audio if this setup doesnt work out.


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## nadams5755 (Jun 8, 2012)

i'd suggest another PCI slot but there's no other slots on the board. maybe put down an ABS plate/shroud over the motherboard, cover the top with some foil. or wrap the card in ABS and put some foil on the outside.

i don't know what signaling frequencies usb 2/3 are, bluetooth is 2.4ghz. if input devices can trigger it, probably right around that rate. i don't know what frequencies the sound card or its power supplies are operating at.

if it seems CPU load-based, maybe try firing up prime95 and see if you can get the feedback constant.

some hdmi cables have poor 2.4ghz shielding which can impact things operating around those frequencies.

you might be able to play around in the bios to disable CPU throttling or maybe underclock the CPU.

maybe you can do 6ch pcm digital audio over hdmi and have an outboard dac which will take the 6 pcm channels to analog for your DSPs.

if you drop it down to 16-bit+44/48k, does the feedback get any better or worse?


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## garysummers (Oct 25, 2010)

I am using JRiver as well for my music app. I have Perfect Surround VST plug-in for my 5.1 upmixing within JRiver.
JRver is the best app I found in my searches and tests. The fact that it allows 3rd party VST plugins and can be set up as the main audio output signal path is great. The way it is configured on my PC any audio the sound card processes is routed through JRiver. That way I can play files off the music library, Itunes, Spotify, Pandora, or my phone and it will all route through JRiver and thus can be up-mixed through Perfect Surround. JRiver also handles my discreet 5.1 files with ease. JRiver has an internal up-mixer but it is not as good as Perfect Surround. Too many artifacts in the process.

I don't see this type of setup possible using an outboard DAC. I originally tried using an HDMI De-Embedder to extract the 5.1 signal discreet audio but it was plagued with more noise issues than the current set-up. Also it was not clear if there was down sampling of the original file.


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## garysummers (Oct 25, 2010)

nadams5755 said:


> i'd suggest another PCI slot but there's no other slots on the board. maybe put down an ABS plate/shroud over the motherboard, cover the top with some foil. or wrap the card in ABS and put some foil on the outside.
> 
> i don't know what signaling frequencies usb 2/3 are, bluetooth is 2.4ghz. if input devices can trigger it, probably right around that rate. i don't know what frequencies the sound card or its power supplies are operating at.
> 
> ...


I have been experimenting with shielding the card from the mobo but nothing has produced a different result.
The noise is present regardless of the bit depth and sample rate.
As I mentioned above I tried an Atlona HDMI de-embedder at first. Had noise issues as well.
Like you said the noise appears to be CPU load based. I am not computer savy enough yet to mess with the Bios settings but that may happen. My brother is deep into computer building and I may have him assist with that.


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## CrimsonCountry (Mar 11, 2012)

garysummers said:


> I am using JRiver as well for my music app. I have Perfect Surround VST plug-in for my 5.1 upmixing within JRiver.
> JRver is the best app I found in my searches and tests. The fact that it allows 3rd party VST plugins and can be set up as the main audio output signal path is great. The way it is configured on my PC any audio the sound card processes is routed through JRiver. That way I can play files off the music library, Itunes, Spotify, Pandora, or my phone and it will all route through JRiver and thus can be up-mixed through Perfect Surround. JRiver also handles my discreet 5.1 files with ease. JRiver has an internal up-mixer but it is not as good as Perfect Surround. Too many artifacts in the process.
> 
> I don't see this type of setup possible using an outboard DAC. I originally tried using an HDMI De-Embedder to extract the 5.1 signal discreet audio but it was plagued with more noise issues than the current set-up. Also it was not clear if there was down sampling of the original file.


I'm with you. I cant say enough good things about Jriver and how useful it is, especially for a CarPC. Gone are the days of having to have complicated audio routing with Audiomulch or whatever given the loop back feature in Jriver.

So what is your exact signal chain? EVGA to 8x12 via RCA inputs? So you're running multiple conversions...sound card DAC and 8X12 DAC? I also see HDMI being mentioned but it sounds like you abandoned that device and are simply using analog inputs. If that's the case, and you're not concerned with only having a single DAC, any multichannel USB DAC should work like the UDAC8. I ran this exact setup and it can be made to work. Mine was noise free as well. Assuming you have the 8x12DL as well, otherwise you could skip the 8x12 outright.

And on your feedback, I would try loading the CPU too to pinpoint the exact issue. I forgot to add I too noticed significant feedback when using the mouse when I had my DSP connected via USB (for tuning) to the PC. It went away when I disconnected it so I assumed it was an isolation issue with it all being tied together at once via USB hub. Is yours always connected?


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## diy.phil (May 23, 2011)

Gary, I met that Sliger (enclosure/case) boss about 20 years ago lol. Back then they did custom metal fabrications. Later some industrial/rackmount enclosures. Lately custom and semi-custom PC cases too. I know you have that nice M4-ATX power board but is it getting the power from a car battery or a large 12V power supply. Maybe is quieter with a car battery(?) and also for tests try a regular atx power supply if it makes a difference. Also maybe temporarily (for tests) try that soundcard in a different system/mainboard if it's any better here.


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## garysummers (Oct 25, 2010)

CrimsonCountry said:


> I'm with you. I cant say enough good things about Jriver and how useful it is, especially for a CarPC. Gone are the days of having to have complicated audio routing with Audiomulch or whatever given the loop back feature in Jriver.
> 
> So what is your exact signal chain? EVGA to 8x12 via RCA inputs? So you're running multiple conversions...sound card DAC and 8X12 DAC? I also see HDMI being mentioned but it sounds like you abandoned that device and are simply using analog inputs. If that's the case, and you're not concerned with only having a single DAC, any multichannel USB DAC should work like the UDAC8. I ran this exact setup and it can be made to work. Mine was noise free as well. Assuming you have the 8x12DL as well, otherwise you could skip the 8x12 outright.
> 
> And on your feedback, I would try loading the CPU too to pinpoint the exact issue. I forgot to add I too noticed significant feedback when using the mouse when I had my DSP connected via USB (for tuning) to the PC. It went away when I disconnected it so I assumed it was an isolation issue with it all being tied together at once via USB hub. Is yours always connected?


The signal path is analog out of the EVGA/Nu Audio card 5.1 to the inputs of a CDSP 8X12 which handles the front stage and outputs a Left Rear / Right Rear analog signal to a second CDSP 8X12 which creates the L-R rear signal to the four headrests. I patched around and eliminated the CDSP's and went straight to the amps for L,C,R, LS, RS and the noise was still there. I do not have the CDSP USB cables in unless I am adjusting the parameters.
Can you elaborate more on what you mean by "loading the CPU too"?
The USB format does not have the bandwidth to pass 6 channels of 24/96khz signal. Thus an outboard USB DAC will not work for this application. Only HDMI has the bandwidth to do this and that proved to have noise as well.


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## garysummers (Oct 25, 2010)

diy.phil said:


> Gary, I met that Sliger (enclosure/case) boss about 20 years ago lol. Back then they did custom metal fabrications. Later some industrial/rackmount enclosures. Lately custom and semi-custom PC cases too. I know you have that nice M4-ATX power board but is it getting the power from a car battery or a large 12V power supply. Maybe is quieter with a car battery(?) and also for tests try a regular atx power supply if it makes a difference. Also maybe temporarily (for tests) try that soundcard in a different system/mainboard if it's any better here.


Sliger seems like a great company. Family owned! I was emailing directly with Kahlin Sliger who designed the case I am using. I have designed this whole install in 3D CAD, so that I could see it in 3D before building. He sent me a 3D model of the SM560 case to design with.
I am testing the system in my house with a Mean Well SE-600-12 PSU. It is putting out 13.5volts which is what my car charger sits at. 
The sound card requires 2 PCIe slots and the other PC I have only has one. The mini ITX form factor does not have many cases that allow two PCIe cards. That was why I went with the Sliger case. It does.


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## garysummers (Oct 25, 2010)

Here are a couple 2D renders from the 3D CAD files. If I could not get a 3D model from the manufacturer, I would create my own to scale.
This box will reside in the trunk under the rear deck shelf. I had a subwoofer there in the past but it was moved to the front passenger footwell.


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## garysummers (Oct 25, 2010)

So I have been troubleshooting this noise issue. If I eliminate the mini DSP 8X12s from the audio path and patch directly from the output of the EVGA/Nu Audio sound card to the inputs of the amplifier the signal is clean. I have everything grounded at the same ground block and have verified continuity for all grounds. I have tried grounding the CDSP chassis to the block and tried it to the case of the PC. Nothing changed. The interesting thing is that if I plug the USB connector into the CDSP, the level of the noise drops. It does not go away completely but gets better. The noise is for sure related to CPU activity, such as moving on screen graphics, mouse movements, scrolling, boot up, shut down activities, etc. If I have the RCA plugged into the CDSP and just touch it to the metal face of the sound card the noise appears. Its like there is DC on the shield or something. I will be the first to admit this is not my area of expertise. I have a a request ticket into MiniDSP Dev team on this issue.
Any other ideas you may have that I could try I am all ears.
Thanks in advance. If more data is required and I will add all I can.


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## Ge0 (Jul 23, 2007)

garysummers said:


> So I have been troubleshooting this noise issue. If I eliminate the mini DSP 8X12s from the audio path and patch directly from the output of the EVGA/Nu Audio sound card to the inputs of the amplifier the signal is clean. I have everything grounded at the same ground block and have verified continuity for all grounds. I have tried grounding the CDSP chassis to the block and tried it to the case of the PC. Nothing changed. The interesting thing is that if I plug the USB connector into the CDSP, the level of the noise drops. It does not go away completely but gets better. The noise is for sure related to CPU activity, such as moving on screen graphics, mouse movements, scrolling, boot up, shut down activities, etc. If I have the RCA plugged into the CDSP and just touch it to the metal face of the sound card the noise appears. Its like there is DC on the shield or something. I will be the first to admit this is not my area of expertise. I have a a request ticket into MiniDSP Dev team on this issue.
> Any other ideas you may have that I could try I am all ears.
> Thanks in advance. If more data is required and I will add all I can.


So, whisper quite when you plug PC sound card directly into the amps. But, you get digital computer noise when inserting the DSP's. Sounds like the DSP's are floating the RCA input grounds. I've had a similar problem in the past.

Try this quick test. Connect the RCA input ground (sleeve) when plugged into the DSP to the power ground input on the DSP. Does the noise go away? If it does, try connecting a 10 ohm resistor in series between the shorted grounds. Is the noise still gone? Finally try a 100ohm resistor in parallel with a 1nf leaded ceramic capacitor. Is the noise still gone?


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## garysummers (Oct 25, 2010)

Ge0 said:


> So, whisper quite when you plug PC sound card directly into the amps. But, you get digital computer noise when inserting the DSP's. Sounds like the DSP's are floating the RCA input grounds. I've had a similar problem in the past.
> 
> Try this quick test. Connect the RCA input ground (sleeve) when plugged into the DSP to the power ground input on the DSP. Does the noise go away? If it does, try connecting a 10 ohm resistor in series between the shorted grounds. Is the noise still gone? Finally try a 100ohm resistor in parallel with a 1nf leaded ceramic capacitor. Is the noise still gone?


Thanks GeO for the quick reply. I am ready to blow this thing up!! 
It will take a bit to try your suggestions as I don't have a stock of the components you suggest. Need to cut up a pair of RCAs for your first suggestion. I have been looking at RCA ground loop isolators just to see if that makes a difference. I had these two CDSPs installed with my F1 Status components and they were dead quiet.
With the system on and everything connected, except the outputs of the sound card to the inputs of the first CDSP, all quiet. So CDSPs to amps to speakers= no noise. I will try your suggestions as soon as I can get the components.


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## Ge0 (Jul 23, 2007)

garysummers said:


> Thanks GeO for the quick reply. I am ready to blow this thing up!!
> It will take a bit to try your suggestions as I don't have a stock of the components you suggest. Need to cut up a pair of RCAs for your first suggestion. I have been looking at RCA ground loop isolators just to see if that makes a difference. I had these two CDSPs installed with my F1 Status components and they were dead quiet.
> With the system on and everything connected, except the outputs of the sound card to the inputs of the first CDSP, all quiet. So CDSPs to amps to speakers= no noise. I will try your suggestions as soon as I can get the components.


You don't need anything but a straight wire to try the first trial. Short the DSP RCA input sleeve to the DSP power ground. Does this solve the problem? 

The only reason behind trying the 10ohm and then 100ohm/1nF cap solutions is to prevent possible damage to your DSP. Just in case there is a substantial current flow between grounds.


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## garysummers (Oct 25, 2010)

Ge0 said:


> You don't need anything but a straight wire to try the first trial. Short the DSP RCA input sleeve to the DSP power ground. Does this solve the problem?
> 
> The only reason behind trying the 10ohm and then 100ohm/1nF cap solutions is to prevent possible damage to your DSP. Just in case there is a substantial current flow between grounds.


Yes, I did exactly what you said. Grounded the shield of the RCA to the power ground of the CDSP. On second test, better implementation, the noise gets louder.


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## Ge0 (Jul 23, 2007)

garysummers said:


> Yes, I did exactly what you said. Grounded the shield of the RCA to the power ground of the CDSP. No change at all.


Also try grounding RCA outputs to power supply ground. Try grounding RCA ground input to RCA ground output. The try linking all the grounds together (input, power supply, output)


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## garysummers (Oct 25, 2010)

Ge0 said:


> Also try grounding RCA outputs to power supply ground. Try grounding RCA ground input to RCA ground output. The try linking all the grounds together (input, power supply, output)


Grounded shield form sound card output to shield of the CDSP input then grounded to CDSP power ground then to ground block. Noise still present but did not appear to get louder this time.


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## Zippy (Jul 21, 2013)

Hi Gary,

Have you tried adding a voltage regulator to the power going to the PC and DSP? I've seen in the past where it's the electrical source causing noise issues on car PCs.


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## Ge0 (Jul 23, 2007)

How much input gain are you adding on the DSP? Just for sh!ts n giggles do you have another brand / design of DSP you can test?


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## garysummers (Oct 25, 2010)

This is the response from MiniDSP Dev Team:

Hi Gary,

Most likely some grounding/earthing issue going on here.. What's your setup? Is that inside the car already or you're doing this test on a bench?

1. Use the shortest ground wire to minimize resistance and avoid noise problems.

2. Keep input-signal cables away from power cables and speaker wires. Use grommets when passing cables through metal.

3.Check the chassis of PC is grounded. (even SSD harddisk, it is easy to create noise, try USB stick instead of SSD)

4. Since the input ground and output ground of CDSP8X12 are isolated, the daisy chain of 2 CDSP8X12 may make ground loop here, you can open the CDSP 8x12 box and try to plug the jumper inside CDSP8X12 to "GND" position.



Hoping this info helps and feel free to contact us if you have further questions.

Best Regards
miniDSP DevTeam

#4 looks like an interesting development in this whole scenario! I can check off the first three as done or verified.
That fact that patching around the MiniDSPs eliminates the noise, checks off #3. #2 is checked! I have measured all the grounds resistive loads and all are good, so #1 is checked off.

So I changed both MiniDSPs jumper to GND. Voila, the noise is gone.


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## metanium (Feb 2, 2007)

garysummers said:


> So I changed both MiniDSPs jumper to GND. Voila, the noise is gone.


Yay! I've been following your "noise saga", and glad you got it resolved.


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## Ge0 (Jul 23, 2007)

garysummers said:


> This is the response from MiniDSP Dev Team:
> 
> Hi Gary,
> 
> ...


That's what my wire check was trying to prove last night. Congrats!!!


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## CrimsonCountry (Mar 11, 2012)

garysummers said:


> This is the response from MiniDSP Dev Team:
> 
> Hi Gary,
> 
> ...


Great news! Glad it was something relatively easy...albeit still annoying to track down.


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## garysummers (Oct 25, 2010)

I was thinking maybe the other settings might make it even better. Here is a photo of the jumpers in the CDSP 8X12.
I asked MiniDSP DEV and they said sure play with other settings.
The one that says "200R" looks interesting. I assume the means 200 Ohms. If that matches the output impedence of the PC better it would be better, correct? 
What do you guys think, worth taking it apart to try?


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## garysummers (Oct 25, 2010)

FYI, Tried the 200R setting and the noise was back.
So the noise is gone in the GND position but another issue has surfaced.

I am utilizing the Penteo16 VST3 plug-in within JRiver Music Center for up-mixing duties.
Now with the plug-in active and I change to a song with a different sampling rate I get a pop in the speakers.
This was not the case previously. I can see the pop on the meters in JRiver. If I defeat the VST3 plug-in, I can switch from any sample rate I choose without the pop. With the plug-in off, I can switch from a 5.1 24/192 file to a stereo 16/44.1k file without a pop. Even if I am switching within the same playlist to a different sample rate I get a pop with the plug-in active. I suspected the sound card but with the plug-in defeated all is happy.
I have no idea the "How and Whys" of VST3 plug-ins and how they work. But now the system is quiet but this issue has "popped" up.
If I can solve this last issue then it gets put in the car!


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## Ge0 (Jul 23, 2007)

garysummers said:


> FYI, Tried the 200R setting and the noise was back.
> So the noise is gone in the GND position but another issue has surfaced.
> 
> I am utilizing the Penteo16 VST3 plug-in within JRiver Music Center for up-mixing duties.
> ...


It's all software at this point and it's control over hardware.

For what it is worth I am experimenting with a twelve channel out PC audio interface using VST plugin's hosted by Equalizer APO 1.2.1. I don't have popping issues.


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## garysummers (Oct 25, 2010)

Ge0 said:


> It's all software at this point and it's control over hardware.
> 
> For what it is worth I am experimenting with a twelve channel out PC audio interface using VST plugin's hosted by Equalizer APO 1.2.1. I don't have popping issues.


I think it may be related to the jumper change on the MiniDSPs. Prior to that change it never popped and I had played with it for many hours. I also have it running on another PC hooked to my home theater system and it does not have a problem. Not until I changed those jumpers did this problem happen. I am going to try some Jensen Iso-Max CI-2RR ground loop eliminators. Explained the situation to an engineer friend at Jensen and this is what they recommended.
Not cheap but if it does not work I can return them. Will have to see if it affects the audio. I have seen these used in many studios so I think they will be clean.
I will install and report back. Thanks for the replies and suggestions.


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## garysummers (Oct 25, 2010)

So I installed the Jensen ISO-Max transformers and the result is the system is dead quiet. It also eliminated a slight turn of thump that I had. No degradation of audio sound quality that I can perceive.
They are here to stay!!


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## MajorNoob (May 10, 2018)

Hello Gary,

it's great to hear you solved the issue! If you don't mind me asking, is there any chance you could give us a rundown on your system as it stands now (with its new PC, front sub and headrest speakers) in the near future? The amount of research and engineering you put into it is fascinating!

All the best.


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## garysummers (Oct 25, 2010)

Installed in the car! 















It will take me a little while to write the whole rebuild up in detail. Some of those details are wrapped up in a patent I have filed so I will need to omit those.


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