On iOS for iPhone 6s (running V9.3.1)
if connect to bluetooth (i.e. connect to a car).
if car is turned off then restarted, the right channel disappears.
have to reboot DJay2 App (running V2.8.1) to resolve issue.
NOTE: iPad Air 2 (running V9.3.1) is not affected.
NOTE: Same issue with multiple cars and bluetooth headphones
Update May 6, 2016 (updated on everything)
I noticed that if bluetooth is disconnected (i.e. Turn car off). When re-connecting, as long as my device is NOT playing DJay but another app instead (i.e. Apple Music app) this problem will not occur.
But if i re-connect while device is playing DJay problem will persist.