5N2 suspect corrupt filesystem

I have a 5N2,

A mixed bag of drives, 2 WD reds, one Tosh N300 (3 x 4TB)

2 older Seagate 250GB.

Was filling up, so I decided to move my time machine backup elsewhere. (This was a 500GB mac share)

I stopped the mac using it and deleted the share.

Lots of activity and after a few hours it rebooted its self.

Now in a reboot loop when in R/W mode.

It is out of warranty, but I logged a case anyway. Support told me about the read-only mode.

This let me boot up and my other shares appeared to be accessible. I started to get my data off.

After maybe 20 minutes it just stops responding to samba and the dashboard

I can still ping it, and i can log on via dropbear.

It comes back online and lets me copy a bit more data after powering off with the button.

I can see it intermittently trying to remove a .TM folder from under /mnt/DroboFS/System/DNAS/deleted_shares (my old time machine chare was called TM)

As /mnt/DroboFS is mounted read-only at the moment I assume it is still trying to clean up the deleted share and failing and falling over for some reason.

When it is working it is copying off at about 100MB/s over gig ethernet, so It seems to be performing OK, but it just hits the wall hard about every 20 mins.

The data on there is replaceable at a push, just a real pain to get it all back hence me trying to copy it off locally.

Any thoughts/ideas anyone?