There has been some anecdotal evidence that jackd2 can also x-run during freewheeling.
This should be impossible…, but jack2 also does other impossible things
I tried to get my system working without JACK but nothing comes out of my speakers. I’ll spend some more time with it and see if I can get it to work and report back.
I guess jackd may still be running and block the soundcard.
In any case I was asking about export (no soundcard is needed for that) just to check if the issue is jack specific or perhaps session or system specific.