Problem with buzz noise comming from speakers

[sibuns]

Ok so i have a technics AV receiver on another side of the room. I have connect it to the computer via usual rca audio cable. When i also have it connected to the tv. From tv there are no buzz comming from speakers. At first i thought that the problem may be in cable because it has quite a lenght in it(around 10-15m). Then i found out if i plug the same cable in the phone instead of computer there is no buzz noise. So buzz noise only comes when connected to computer(at the back on motherboard).

Because i have no buzz sound in headphones(they are plugged infront), i thought that the back connector might have some problems. So i plugged the receiver in front jsut like headphones are... Still the same problem...

Is there a way to fix it ?

 

[americanaudiophile]

You have a ground loop from the PC to the receiver. You can check this by lifting the ground on the AC of the receiver. You aren't supposed to do this permanently so get an audio isolator.
https/www.radioshack.com/products/radioshack-ground-loop-isolator?gclid=EAIaIQobChMI0Y-cnPLF1QIVm4izCh2SigDnEAQYASABEgJRyfD_BwE