Update to this, which might help in diagnosing, might not.
I can ensure that the bluetooth A2DP connection will successfully deliver audio to my headset consistently if I switch back to "Headset Head Unit (HSP/HFP)" mode in Sound settings prior to disconnecting the headset.
Then, next time I connect the headset, it will be in "Headset Head Unit (HSP/HFP)" mode, but when I switch to "High Fidelity Playback (A2DP Sink)" every single time it successfully plays back audio.
Update to this, which might help in diagnosing, might not.
I can ensure that the bluetooth A2DP connection will successfully deliver audio to my headset consistently if I switch back to "Headset Head Unit (HSP/HFP)" mode in Sound settings prior to disconnecting the headset.
Then, next time I connect the headset, it will be in "Headset Head Unit (HSP/HFP)" mode, but when I switch to "High Fidelity Playback (A2DP Sink)" every single time it successfully plays back audio.