Not so happy with the m8.

Mine, did this. I rebooted plugged and unplugged various headset and did not go away, I thought maybe sweat from working out had got in it because within a couple of hours it went away and have not had the problem since.

I also decided to just use bluetooth headphones from now on though as I am afraid to plug in a headset.
 
Same thing been happening to me I reboot and most of the time it fixes it.

Sent from my HTC One_M8 using Tapatalk
 
I've rebooted several times with no luck! It will go away for a few minutes, but it alwayscomes back on. HTC has been less than helpful.