Thanks for the answers, sorry if I havent been clear, as English is not my native language.
I have two separate problems.
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First: NOISE
- This is a mild but very hearable intermittent hisss, hisss, hisss on the left channel.
- This is present all the time, even when not playing any music, independent of format, OS or USB cable.
- This happens using both headphones or RCA output.
- The problem appears to be internal to the uDSD as it happens on THREE DIFFERENT COMPUTERS: one desktop PC with Windows 10, one Ubuntu laptop and one Mac Book Pro with Mac OSX, I have tried with two different USB cables.
So, it is not a problem with the computer, it is not a problem with the cable. I can only infer it is a internal problem to the board. I don't think its physical connections as it happens on both rear ports as well as headphones.
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Second: DSD playback
I agree this is probably configuration, but playing DSD with JRiver and all the configurations listed on the NuPrime PDF for DSD with JRiver (which by the way has an incorrect link on the new page design, I had to google it to find it) produces a COMPLETELY DIFFERENT type of noise: a very LOUD digital noise from both channels. This is the typical noise of a DAC receiving a format it doesn't understand, just like when you send dolby signals to a PCM only device. That type of noise. I would appreciate the walk through to have the proper configuration, although I am not a newbie in any way, I'm a software engineer, so please consider that the 'obvious' thing I may have probably already tried. Of course, I could have missed something obvious.
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There is very slim chance that both of this problems could be related and that the 'perpetual' mild noise is a residue of the same issue that is preventing the DSD from playing correctly, but I highly doubt it.
I could provide recordings of the different scenarios if it helps.
Thanks again, best regards,
Rafa.