My Pavillion x360 has a combo 3.5mm jack and an internal microphone. I plugged my headphones into the combo jack and used the standard internal mic for Skype. I noticed that this causes feedback into my headphones whenever my friends aren't talking.
This static-like noise just gets larger and larger, until someone makes a noise (presumably breaking the feedback). I'm not sure what to do here to stop the problem, but I'm sure it's the feedback causing it because I've tried several headsets, and the only thing that works is to use both the standard internal speakers and the internal mic. I can't use headphones, or a headset without feedback.
Does anybody have any ideas for things to try?