[20:03] <chris_uk[m]> * Just tried the new 21.10 beta and managed to get Ardour working, booting from live USB. Had to select Jack to do so. I imported and played an MP3 file OK. The Ardour splash screen seems to stick at 'loading' and again at 'configuring audio and midi engine' stage  but if I click on it, it disappears and I can proceed. I assume this may be because I haven't installed it yet and the slowness of booting from a live USB. 
[20:42] <Eickmeyer> chris_uk[m]: I'm pretty sure that's not a bug but a feature as the same behavior is in Harrison Mixbus (Ardour's downstream paid project). You can alwasy ask in #ardour:libera.chat