I've rerun the parity check after rebooting, and attached the resulting diagnostics ZIP file. Here's the relevant snippet from the syslog:
Feb 2 01:30:01 SageTV kernel: mdcmd (42): check
Feb 2 01:30:01 SageTV kernel: md: recovery thread: check P ...
Feb 2 03:12:23 SageTV kernel: md: recovery thread: P corrected, sector=2353004440
Feb 2 03:12:23 SageTV kernel: md: recovery thread: P corrected, sector=2353004448
Feb 2 03:12:23 SageTV kernel: md: recovery thread: P corrected, sector=2353004456
Feb 2 03:12:23 SageTV kernel: md: recovery thread: P corrected, sector=2353004464
Feb 2 03:12:23 SageTV kernel: md: recovery thread: P corrected, sector=2353004472
As you can see, the corrected sectors match the last parity check exactly. Hopefully, this gives a clue as to root cause of the problem and suggestions on where to go from here. If the drive(s) are good, and this is strictly an issue with the SAS2LP controller card, I can replace the card with an LSI 9207-8i and resolve the issue. However, if I have issues with the parity drive that requires replacing the drive, that will be a more costly remedy.
Suggestions?
sagetv-diagnostics-20210202-2040.zip