Macbook Pro microphone randomly

Hi!

I have a 13 inch macbook pro retina late 2013 edition.

I recently noticed that the microphone would mute during a call on skype/teamspeak when i have my headphones (tried multiple pairs, astros, iphone headphones, senheiser)

There will be no indication. ie. nothing saying microphone is muted.

I would only find out im muted when the other party tell me that if I was still there.

However the problem goes away, if i unplug the headphone and plug it back in again.

Any ideas to what has happened?