Microphone issues with loud buzzing/robotic sounding voice

A friend of mine recently started to have speaker/microphone issues (sound would cut out at times for her speakers and mic, had to position herself perfectly) and eventually the speakers completely died. She got a new set (Earbuds + microphone on the cord) and that worked fine for a few hours. Eventually, there was a buzz on her end and her volume (voice) got considerably lower. The buzz wasn't that bad, so we just changed the volume/mic volume to fix it, and the next day it was gone.

Sadly, at the end of the next day, the mic started to buzz again, except worse this time. It was nearly impossible to hear her over the buzzing sound, but we both went to bed soon after that. The next day was the same thing, but again it got worse. This time her voice would sometimes distort into static/robotic sounds. When it was loud enough, it was at least somewhat understandable.

On day 5, and her mic started off buzzing today. She switched to the old microphone (plugged the yellow cord into the yellow jack) and her voice was fixed for a few hours. She went out for a few and came back, but when she did she couldn't hear me and I couldn't hear her. We've tested extensively (restarting, using other programs, she can hear it herself when it's recorded/played back, the other mic jack doesn't seem to notice when it's plugged in + is unreachable sitting normally, and of course plenty of wire jiggling. After all of this, her voice would cut in and out of the robotic sounds, and the buzz would be extremely loud or nearly non-existent while she would be sitting completely still besides talking).

We have very little idea as to what's causing it. This is all over Skype but happens (to a lesser extent possibly) with other programs, so it's for sure a microphone/computer issue. Any help that can be provided will be appreciated.