Merely starting kdenlive on windows 11/23h2 without any audio output devices (= disconnected bluetooth headset) right after installing it leads to UI freezes that last many seconds and happen all the time, on startup, when trying to load a file, basically when doing anything. It is basically completely unusable. Switching the audio device to auto in kdenlive does not help. This affects 23.08 as well.

It took quite some time to figure out that

* just turning the headset on is enough to fix this
* OR changing the backend from SDL to RtAudio 

because I first suspected HW acceleration, general performance issues, ..