Headphone and Analog are two separate on the Desktop TI, sorry about the mixup! :)

Tried a short ferrit core USB cable, tried wiring
the Snow and the RME and my PC. No luck, the noise is still there....

If it were me, I would try narrow down the cause.
Can you hear that noise with headphones without the RME plugged in to your PC or Virus?? (totally remove the RME from the room).
That sound was very faint so maybe it is hard to do.
Next, can you hear that noise with the Virus plugged into your RME but not into the USB of the computer??
When you answer these you can say Yes or No to 'does the Virus make this noise all the time?'
Then you could consider work arounds like. Try an analog mixing console between the RME and Virus, also try passive DI boxes between the RME and Virus. (GRS hears googling of passive di boxes).
:)

there is nothing wrong with your set up VC sucks big time & everyone knows it...the usb cable will not resolve your issue, maybe buy a hub or pci usb card or just use it 'as is' trust me it is a LOT less headache than trying to make this piece of crap software work...8 years & it still sucks!

Well, I bought an USB Isolator, this did the trick,
kind of like an DI Box for USB. It cost me 99 € and I really dont like paying extra money for something that should have worked in the first place.
But it does now, so the case is closed, at least for me.
This has never happened to me before and I hope it never will again!

Great to hear you found a solution. My guess is the PC is the root cause. You may find in the future if you upgrade your PC you might not need the USB isolator. PC power supplies range in quality a lot. That behringer DJ controller problem I had went away with a different laptop.

This might be right, but the Snow was the only troublemaker,
everything else, going in via USB, other synths works perfect.
The PC and all its hardware components are 1 year old.
And since this noiseproblem seems to be very often with the snow according
to forums, I figured its not my PC.
But again thanks for all help!

This might be right, but the Snow was the only troublemaker,
everything else, going in via USB, other synths works perfect.
The PC and all its hardware components are 1 year old.
And since this noiseproblem seems to be very often with the snow according
to forums, I figured its not my PC.
But again thanks for all help!