Well after months of failed backup jobs its here. The patch i’ve been waiting for:

http://www.symantec.com/business/support/index?page=content&id=TECH147674

The error i got was: V-79-57344-38260 – Unable to create a snapshot of the virtual machine. The virtual machine may be too busy to quiesce to take the snapshot.

For some machines reinstalling vmWare tools without filesytem sync driver solved the problem. For others it didn’t. I’ll update the post as soon as I upgrade the media server and agents.