I got a speaker system a few weeks ago, Logitech Z313, and whenever I use them on my PC they sometimes make a high pitched static noise. They could be quiet for a minute and then it comes up again for like 5-20 seconds. The static noise starts suddenly and gets louder until it reaches a point where it goes quiet again. If I turn the speaker's volume wheel up, the sound gets louder. I've also noticed it's louder when in-game. The speaker system has a port where you can plug your headset in so you don't always have to switch and when I plug my headset in there, it also has this background static noise, which the headset normally doesn't have (when plugged directly in the PC). It's really frustrating. Can someone help identify the source of the problem? Thanks!