Bus Error (btrfs) without changes

The service is crashing without any changes. It was running fine for about a month but today it started crashing. Couldnt find any useful error message. Debug says its bus error.

OS: Debian 12 bookworm
Server Version: v2.5.33.0
backup folder is mounted at /mnt/backup/ btrfs [defaults, compress=lzo, autodefrag ]

$ df -h
udev            1,7G     0  1,7G   0% /dev
tmpfs           352M  2,1M  350M   1% /run
/dev/sda2        23G  2,9G   19G  14% /
tmpfs           1,8G  1,2M  1,8G   1% /dev/shm
tmpfs           5,0M     0  5,0M   0% /run/lock
/dev/sda3       9,1G  3,3G  5,4G  38% /var
/dev/sda5       1,8G  164K  1,7G   1% /tmp
/dev/sda6       181G  9,1M  172G   1% /home
/dev/sda7       3,5T  573G  2,9T  17% /mnt/backup
tmpfs           352M     0  352M   0% /run/user/1000

urbackup.log (4.7 MB)