With Poweramp You have 1. trial version which is also the full app once ulocked and 2. Poweramp Full version unlocker.
When in poweramp go to settings > audio > output > Hi-Res Output: activate BT.
Also make sure to check off DVC:
Hi i am currently using the unlock version of Poweramp.
Thanks for tips. I have just activated the Hi Res output for both BT and USB DAC.