This morning when I plugged in my DT990 the left earcup was producing no noise and so I thought it might the amp I am using, Fiio E9, but I tryed some different headphones and made sure it was not the amp. I then plugged my headphones into my phone and the left driver was indeed making no noise
I lightly tapped on the earcup and it started back with audio again, but after 5-10 min it would go out. After 6 or so times of tapping the earcup that would no longer work, and I have no audio in the left earcup, even at the max volume on the amp.
I think it could be an issue with the wiring or something, please help!