I just trouble-shooted a pretty sneaky issue with connecting my HTC U11 (using the latest Android 8.0 ROM update) my car’s bluetooth receiver. Apparently, the „skip to next/previous track“ buttons/controls stayed inactive, despite the actual playback working properly.
I then tried a couple of things and found out that you had to switch the version of the bluetooth AVRCP from 1.4 to 1.6 in the Android developer options(!) in order to get the controls active & working again.
That’s rather unintuitive and mind-boggling for a current smartphone.
I wish hadn’t to do this.