Just wanted to say I had this issue on both Intel and M1 Macs. Time Machine backups to Unraid were going swimmingly, with the Unraid share hosting an APFS sparseimage. I'm not sure if it was the Unraid 6.10 update or MacOS 12.3/12.4 or just bad timing, but then all the computers stopped being able to back up a month or so ago. I was able to make first (non-incremental) backups without issue, but subsequent incremental backups after that did not work. I had the same MacOS console issues as mentio