ipod disconnecting

[danturn]

my third 20gb ipod 3rd gen i think (2nd replacement from apple after 1 died and the case for 2 was really really ill fitting!) has started randomly unmounting, i put it on the dock, it mounts but after a little while it will just dismount. im sure i have heard about this before but cant find the stuff again!!!

any ideas?

i run a P4 2.2ghz 384mb ram XP etc etc.

thankks