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USB noise

korhanerel
So after posting, deleting and checking again, I can confirm that there is a quiet, high-pitched sound coming from Kodamo when it's connected over the USB B port. I thought the synth was designed to eliminate this. I wonder what I'm doing wrong.

Thanks
KODAMO
Hello,

I think there's a ground loop in your setup, the audio outputs of the EssenceFM cannot create that as they are fully isolated. That usually means that you can connect the EssenceFM to unbalanced gear without any problems if the audio goes into the same device that provides USB. But if it's different devices, or if they are in turn connected to other unbalanced equipment, ground loops may be created at other points (the USB port of the EssenceFM is earthed). Usually the best solution is to only use balanced (TRS) jacks and devices.

Can you explain how your setup is wired ? (describing each device, audio connections and power connections)
korhanerel
Indeed there was and it's solved now. Thanks.
korhanerel
Please feel free to delete this post, as it's not relevant anymore.
Babadin
Hello, I too have this problem : it's a high pitch noise when I plug the USB from the Kodak to my computer.
My setup is :
- Kodamo audio outputs go to a FocusRite Scarlett used as an ADAT module
- Kodamo USB is plugged to a Mac mini M1
- FocusRite Scarlett optical out is connected to a Universal Audio Twin X (as ADAT)

I put TRS cables on the Kodamo - so as long as USB is not plugged, no noise.
But when I connect the USB on the Kodamo to my computer - or to a USB hub before, the high pitch noise appears.
Do you know how I could solve my problem ?

Thanks a lot,
Christian
KODAMO
Hello,
You likely have an almost complete ground loop somewhere else in your setup and connecting the USB on the EssenceFM is closing the loop (the problem cannot come from the EssenceFM itself as the audio output ground isn't connected to anything else)
Do you use monitors ? Ensure they are also connected using balanced cables.
Babadin
Hello, you're totally right ! That was exactly my problem, my monitors made a ground loop ; I replaced old jack cables with TRS on the monitors, and the noise has gone !
So unrelated to the Essence, thanks a lot for the solution !

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