Similar bug occurs on ze554kl 7.1.1, but apart from described above, sound changes direction to speaker after notification rings. Pulling out and in headphone plug returns sound back to socket. Some rom updates coming in, but event is stable. Turning off dvc partially solves bug, but sometimes player gets hang after ring of notification, send you mail report. I hope, you read them. I use Poweramp from 2011 year, it was excellent product, still android 6 has away.