@ZolaIII As you anticipated, I'm having problems with groundloops and I'm trying to solve them.
Quick recap of the situation:
In the end I bought kali lp 6, i connected them to my pc and i hear a buzzing sound which become even more annoying when moving mouse or doing anything with my pc.
I tried to connect them to my macbook and there is no buzzing sound/noise at all.
I understood that the problem was coming from my pc and i quickly purchased a DAC (S.M.S.L SU-1) which i thought would solve the problem...well it didn't.
Everything is connected to the same power outlet (i don't have the possibility to connect to different outlets).
What should I do to solve the problem??
I'm reading online about several methods, but i can't figure out which one would be the most suitable for my condition