Hi Ralf, can you attach the complete dmesg log to the bug report, please? I see a snippet (starting with "Bluetooth: SCO socket layer initialized"), but there's a lot of useful information before that. The "dmesg" command only shows the most recent part of the log, so if the kernel's buffer has wrapped around, it doesn't show the beginning. The /var/log/dmesg (or similar) file should contain the useful bits.