[build 793-play] BT issues, OpenSL and track metadata

[Spacebrain]

Hi,

I'm experiencing some bluetooth-related issues with this new build of Poweramp (running on an Xperia Z5, Android 7.1.1)0

• I had to change Bluetooth audio output to AudioTrack, OpenSL ES is giving me skips and stutters.
• On my car head-unit, when I connect my phone through Bluetooth and start playing music, the metadata on the first song (track name, artist and album) are transmitted just fine but it doesn't show up other track metadata until I close Poweramp and re-open it

Thanks for your help and for this very promising update