PCM2706 to PCM1794 help needed

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Tried again today after having swapped to a different vreg for the +/-12Vdc.
I've also "re-flowed" many of the solders.

Swapped back to the PCM2706, used a single PCM1794 board.

With wasapi and asio I got faint audio, and alot of noise.

When trying to feel if the USB-cable was properly connected, I noticed the noise, and unfortunately the audio, went away just by me holding the cable or touching it.

Should I connect RCA gnd's to star-gnd? For now the only thing connected to star-gnd is the IEC sockets earth pin.

Maybe I should run PS gnd and/or signal gnd to star-gnd as well?
 
Given grounding some thought.

I'm not sure how to best do the grounding in this build...

I've attached a draft with some questionmarks to illustrate where I'm at, and how wrong I may be.
 

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Well, I tried that grounding.
Still no-go, noise over very faint audio.

I've tested voltage at the jumper pins and there's +3.30Vdc where it's supposed to be.

I am using a very long USB-cable and there's a wireless router not too far from the DAC, but should that make that much of a difference?

I took gnd to the star-gnd from the USB-connector on the PCM2706, don't know if that is correct?

In the attached pic, I think the +5Vdc and GND is wired the wrong way around, but I caught that sloppy error before powering on the DAC.
 

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It looks like there's a ground loop. If all of the grounds connectors on the PCM1794 board are connected (as they should be), you have a ground loop by running everything to the star ground.

If the USB ground is connected to the output ground of the USB board, you don't need the star ground board at all.
 
I had the same result before trying the star-gnd.

I'll look at the PCM2706 board tomorrow to see if USB connector is connected to output gnd of the board, but I think it is, via gnd-plane.

The reason I tried the star-gnd was to try and remedy the noise.

Could it be the dac having trouble locking on the signal?

Foobar only allows for 16bit 41-48khz.
I've tried asio, wasapi and default "USB-speakers".

Tried the dac board(s) with another reciever, WM8804 fed from a Squeezebox V3 (slimdevices), with the same result.

I know the +3.3vdc works, I'll measure the onboard +5vdc as well.
 
I hope you're feeling better.

I realized after you posted that you had mentioned it.

Can you post the voltages at every pin of the PCM1794 with regards to ground?

I'm still feeling under the weather, or how the saying goes.

I'll try to get to that one of these days, tomorrow we're going for the first ultrasound of our first baby. I'm nervous and very excited...and I have a fever lol
 
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