• Registered: 2018-09-23
  • Posts: 24

Topic: Noise from the USB Connection

I've been having a problem lately. I hear a soft humming from the speaker when I have connected the USB cable in the ADI-2. Is that normal? I am using an active extension for the USB cable. Could this be the reason? Does anyone know the problem? I tried to clean up the USB signal with an ifi iSilencer, but it doesn't help.
Sometimes it even happens that the humming adds a high tone (about 14 kHz). It's all very quiet - but depending on the audio material it's still audible.
I operate the ADI directly on a power amplifier. If I work in the pure preamp mode, without USB cable - all noises are gone...

2 Reply by sebabe (edited by sebabe 2018-09-23 22:35:39)

  • Registered: 2018-09-23
  • Posts: 24

Re: Noise from the USB Connection

Small update: I do not hear any noise on the headphone 3/4 output with Sennheiser HD600. I wonder if the noise problem came with a firmware update - can not remember that there was the same noise in the beginning. ( I did the first FW update recently, before  I used (I guess) V.76 (?)

Regards
Sebastian

  • ramses
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  • Registered: 2012-10-14
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Re: Noise from the USB Connection

sebabe wrote:

I've been having a problem lately. I hear a soft humming from the speaker when I have connected the USB cable in the ADI-2. Is that normal? I am using an active extension for the USB cable. Could this be the reason? Does anyone know the problem? I tried to clean up the USB signal with an ifi iSilencer, but it doesn't help.
Sometimes it even happens that the humming adds a high tone (about 14 kHz). It's all very quiet - but depending on the audio material it's still audible.
I operate the ADI directly on a power amplifier. If I work in the pure preamp mode, without USB cable - all noises are gone...

How is it without active USB extension ?

BR Ramses - UFX III, 12Mic, XTC, ADI-2 Pro FS R BE, RayDAT, X10SRi-F, E5-1680v4, Win10Pro22H2, Cub14

4 Reply by MC

  • MC
  • MC
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Re: Noise from the USB Connection

Please search for 'Intona' in this forum.

Regards
Matthias Carstens
RME

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  • From: Milan, Italy
  • Registered: 2018-09-15
  • Posts: 33

Re: Noise from the USB Connection

I have a similar probler: you may want to follow this discussion https://www.forum.rme-audio.de/viewtopic.php?id=27649

DAW: W10 mini PC (i5)
Server: JRiver 30+Dirac+Acon Declick
DAC: RME ADI2 PRO Speakers ATC SCM50ASL
  • Registered: 2018-09-23
  • Posts: 24

Re: Noise from the USB Connection

Thanks MC! That could help - but sad that there is no cheaper solution.. Still wondering a bit why the noise is not audible with headphones...
(Nevertheless - even with the noise, I need to say it: The ADI 2 Pro FS sounds really amazing. I am going to replace my Linn Streamer and Preamp with this lovely small device... really impressive. Especially in combination with Audirvana player software)

7 Reply by Timur Born (edited by Timur Born 2018-09-25 08:56:33)

  • Registered: 2008-01-01
  • Posts: 3,025

Re: Noise from the USB Connection

Headphones are not grounded and the noise is not originating from the ADI-2, that's why you don't hear any noise on headphones.

A cheap solution would be to break (disconnect) shield on one side of your balanced cables, on XLR this is pin 1. This can make the cable more prone to RF interference (turns into an antenna), but usually having one side connected is good enough. Try the speaker side of the cable first.

8 Reply by bejoro (edited by bejoro 2018-09-25 11:50:29)

  • bejoro
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  • Registered: 2017-03-16
  • Posts: 300

Re: Noise from the USB Connection

Network cable (LAN) connected to the PC/Notebook/DAW can cause ground loop problems and noise. It is recommended to use UTP network cable (Unshielded Twisted Pair) between network switch and PC/Notebook/DAW.

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