I have been having this same problem in the past few days when the temperature warms up above 80f.The player freezes on the W--- icon while accessing the drive and on reboot I get the No Hard Disk error. If I leave the player off for a few minutes everything works fine for a few songs until the player warms again.
I have had both hard drives replaced, the IDE header resoldiered and the older style drive cable replaced/repaired at Cambridge a few years back when it was still under warranty . I am 'pondering' if a drive may be failing under higher temperature conditions. Since I am short on space anyway on the two 30gb drives anyway maybe I will start searching for some new drives and use the backup empeg until then...
Sean in NC
_________________________
_____________
Sean in NC
130gb MK2a w/ 32mb ram
80gb MK2a empeg spare