The oem rom and 3 other roms I have tried also have the same problem. The one M8 does it perfectly, and so did the other phones I've used in past months.
I don't see anyone complaining about this so I'm thinking most people will watch a movie or show without BT headphones. This is my second one max and I I'm ready to return it and go with something else. The one max is perfect size for me because it's replacing my ipad, but with this problem I just can't keep this thing.
If you have a stereo BT headset can you please see if this happens to you?
Thanks in advance.