Netbackup 5.0mp4 on Solaris 9 attached to an L700.

I have a media manager which is connected to shared drives running SSO
on an L700. All drives are up and visible.
I kick a job off and it finds tapes, puts them in and start to position
them but then times out and gives status 52.

I have tried freezing the tapes so it uses different tapes.

vmdareq on the master shows the media has reserved 2 of the drives, and
the tapes are actually being put into drives as i can see under robtest
and 's d'.

Any 52 ive ever had before has been not able to see drives, drives down
or the processes not running. Anyone any other ideas where to look?

Cant see anything obvious in bptm log on the media server. Occasionally
theres an "unable to lock media offset" something error but the rest all
looks ok.

Dave