Hi Stefan, >>> Meanwhile i will play with modifications of original patch on the >>> Raspberry Pi 4 and come back to you. > > could you please test this patch [2] on top of current bluetooth-next? > > This is the solution in case we don't find the cause of this issue. I > don't prefer this one, because this is next stuff and we need to revert > the offending patch for Linux 5.5. > > [2] - https://gist.github.com/lategoodbye/3d39e4b07d401f07fa9f9c2f11e1f17d that patch looks fine to me. Just submit it and we will see how it works out. Regards Marcel