[NTLUG:Discuss] Drive becoming read-only after 40 minutes?!?

[Steve Baker]

Thanks to everyones help a week or so ago, I have my HP Pavilion laptop 
sitting here with it's harddrive removed, booting SuSE 10.2 from a 300Gb 
UDB drive.  It boots OK, runs just fine for ~40 minutes then quite 
suddenly any access to the drive produces a message saying that I can't 
write to the drive because it's read-only?!?   I can still read from the 
drive - and Linux seems to be running just fine (except for anything 
that involves writing to disk.

I've disabled power-save stuff wherever I can find it - and I even tried 
writing to (and 'sync'-ing) the USB drive every 10 seconds with a little 
shell script to make sure it doesn't go to sleep on me.  Nothing helps.

The 'mount' command still says that the disk is mounted R/W -  but every 
disk access produces a write-protect error.

Rebooting the machine gives me another ~40 minutes.

Help!