We've had a recurring issue with one of our appvols 4 2103 deployments. Periodically it will get stuck running through the system jobs - usually during Sync Computer.
Looking at the manager logs there's entries stating:
'Unable to find AD entry for computer domain\IT23253234$ with objectGUID XXXXX"
It appears that template machines are being sync'd? We have a list of pending actions that can't complete because the refresh computer task has not completed. It's not clear how this happens either - we often clear out the pending tasks (via ruby console kill task cmd) and restart the appvol services and this will clear the problem.
Any ideas?