Strange one to get your teeth into...

[Wazhead]

Right, this is an odd one that defies logic.
I found the ONLY way to remove screaching from internal audio (and external DAC linked by USB) was to remove the ground from my PC PSU. I tried absolutely everything else. I then thought 'If I attach a ground from the earth pin of a socket to the case, then the buz will come back'...but it doesn't!
I know I can't really run a PC without a ground, but would it be okay to do so but have a separate ground through a different wire? It just seems to strangely work!
Anyway, any help to ease my befuddled mind would help me sleep tonight.
Thanks in advance.

 

[Gabriel Pike]

It sounds like you have a ground loop happening. There is a device called a ground loop isolator that may help in your situation. I had a similar situation years ago being a mobile DJ and connecting a PC to a PA system.

 

[Wazhead]

Thank you dude. I'll look into it.