Massive-Part

This ground loop noise isolator (https://www.amazon.co.uk/AUKEY-Ground-Isolator-Systems-Included-Black/dp/B01LYYRT7M) has completely removed the background noise.

I've just tried passing the audio through this: https://www.amazon.co.uk/dp/B01CZVCYU0/ as I had one laying around. It seems to noticeably reduce noise issue 1 and completely resolve noise issue 2. I expect using an actual ground loop isolator might do the trick. I'll get one bought and see if it works. Thanks

I have recently built my PC and have had some issues with the audio, sorry if this isn't the right place to post. I am using two Rokit KRK 5 monitors plugged into separate outlets. I have a MSI X570-A PRO motherboard and am using a XFX RX 5700 XT GPU. The monitors are connected to my PC via a RCA to 3.5mm jack. There are two different audio issues that I am having. When playing a game, there is a loud intermittent noise coming out of the monitors. I have attempted to limit the fps and use v-sync to alleviate this. Using v-sync acts to change the rate of the noise, but does not remove it. When I minimise the game, the noise disappears. Using a set of headphones reduces the volume of the noise, but does not remove it. When the PC is idling, there is quieter, but still present noise. Unplugging the 3.5mm jack and placing it into my phone removes this noise. Considering the noise can be mitigated by plugging the cables into another device (my phone), I don't think that cable interference could be the issue. Since the monitors are plugged into distant and separate outlets ground loop interference shouldn't be the issue? I'm pulling my hair out (mainly due to the first issue) as playing games in unbearable when using audio through my monitors. Does anyone have any ideas as to how I can fix this?