LUKS on shutdown.

I'm having an issue shutting down. Fedora 34, just updated to 35, same problem. (It was around in 33 as well, I've been putting up with it.) I know that there is another list for beta versions, but this issue was there in the current version as well. Somewhere around 1 out of every 10 shutdowns, the system goes down to "[ OK ] Reached target System Shutdown", but then, "[ *** ] a stop job is running for Cryptography setup for luks-<cycle through LUKS volumes>" It typically goes for about 1/2 hour if I don't get fed up, and hold the power button down. I just saw after that 1/2 hour: [Time] Timed out starting System Reboot Forcibly Rebooting: job timed out. audit: type=1334......... I still had to power it off. On reboot, it seems OK. I haven't found anything interesting in /var/log/messages regarding it. Any suggestions to further troubleshooting? Thanks, --murph