Fail to backup my settings

I'm running firmware 5.2 (used Seas0npass to jailbreak) on my ATV2 and want to update to 5.3. Unfortunately the backup of my settings takes forever ending with a restart. Tried may times with same results and no backups located in the "Restore from backup" section. The type of backup is set to normal. The ATV2 is connected wireless. I've just sent a diagnostic info, serial number DCYDPHZBDDR5. I already cleared syslog file and cache folders as indicated by Firecore support with no success. Anybody else had this problem? Any solution?
Thank you for your help.