bluetooth mic?
I would think that's the issue,try I mic thats wired,or second best a USB mic,personally I would use a wired mic but I bet you see your issue go away.
You can pick up a cheap headset and give that a try,or beg,borrow or steal one just to test,do the tune to yourself and see if it doesnt clear up the issue.
USB and bluetooth will steal cpu cycles and not take advantage of onboard or a sound card.
I bought a cheapy headset for 20 bucks at wally world and it works fine,doesnt compare with my good set for sound but I used it to trouble shoot and then connected it to a second machine.
Give it a try and plz report back.