Is there an application implementation of A2DP (sound over BT) on Android? Does the OS have problems with this?

Question

Android

How to fix A2DP in Unofficial CyanogenMod 12 for Xperia U ?
Since I personally do not understand firmware and will not go inside to fix, the only solution is in the header (unless you are generous enough to take the time for a stranger to fix the firmware for him).
The developer of the Unofficial version publicly refused to fix:

NOT WORKING:
- A2DP (won't be fixed)
...

I would like to listen to music, but apart from the BT headset, there is nothing suitable.