During the last few days I've noticed that in a small percentage of sessions, about 10-20%, the reliable stream will stall after around 18 KiB of data. Because of the difficulties of reproducing it I was not able to experiment and find the reason yet.
The implications are obviously bad for a reliable production environment like a deployed game, but since it always seems to happen at the beginning of a session after a fixed number of bytes it may not be too bad.
It may have to do with the bluetooth session timing out, or being unable to be resumed. Or it could be an application error. I'll investigate this further and will post my findings.