Question Nintendo Switch causing buzzing sound through speakers

[Zincous]

So I have my Nintendo Switch hooked up to my Logitech Z333 speakers and I can hear a buzz coming through the speakers. The speakers allow for 2 connections at once so I also have it hooked up to my PC. The PC is connected via 3.5mm jack and the Switch via RCA to 3.5mm (just bought this cable, it's the AmazonBasics one). If I unplug the cable from my PC it stops but I want both to be in at the same time. However, if I have both plugged in and I undock my Switch, the buzzing stops, so it only happens in docked mode. If I have the Switch plugged in and I plug the 3.5mm jack that was going into my PC into my phone, the buzzing goes away. Conversely, if I have my PC plugged in and I take the cable from my Switch and plug it into my phone, there's no buzzing. So the problem has to be my Switch, right? Why would the Switch be causing this buzzing while docked?

 

[Ralston18]

Ground loop.

References:

https://www.siber-sonic.com/electronics/GLoopwhatis.html

https://www.w8ji.com/ground_loops.htm

 

[Zincous]

Ground loop.

References:

https://www.siber-sonic.com/electronics/GLoopwhatis.html

https://www.w8ji.com/ground_loops.htm

Thanks, just bought a ground loop noise isolator. Hope it helps!