I'm gonna take a guess and say you're using OBS to record then upload to youtube? I'm using a knock-off "easyCap" usb recorder for my ps2 footage. While searching for videos I did find one that really help get rid of the hum and eliminate the issue completely. You'll want to make sure you add a noise suppression filter to your gv-usb2 audio source. I have mine set to -30dB, hope that helps :)