I got this the first time yesterday (I've had this empeg for about 6 months now).
The message I got from the serial port when failing was:

...

empeg single channel IDE

Probing primary interface...

hdb: TOSHIBA MK1814GAV, ATA DISK drive

ide0: unexpected interrupt, status=0x80, count=1

ide0 at 0x000-0x007,0x038 on irq 6

hdb: TOSHIBA MK1814GAV, 17301MB w/0kB Cache, CHS=35152/16/63

empeg-flash driver initialized

smc chip id/revision 0x3349

smc9194.c:v0.12 03/06/96 by Erik Stahlman ([email protected])



SMC9194: SMC91C94(r:9) at 0x4008000 IRQ:7 INTF:TP MEM:6144b MAC 00:02:d7:22:08:3

6

Partition check:

 hdb: hdb4

RAMDISK: ext2 filesystem found at block 0

RAMDISK: Loading 320 blocks [1 disk] into ram disk... done.

VFS: Mounted root (ext2 filesystem).

empeg-pump v0.03 (19980601)

Press Ctrl-A to enter pump...VFS: Cannot open root device 03:05

Kernel panic: VFS: Unable to mount root fs on 03:05

03:05 is I believe /dev/hda5

Opened it up and tested various configurations of single/dual drive, which contact on the cable that was used etc, but couldn't draw a conclusion from that.
It would get the "Disk not found" about 2/3rds of the time with both disks connected, but it worked with only one disk (so probably not the same problem as the original poster in this thread, as a 20GB (from factory) only has one drive). No amount of pressing on contacts, flexing the cable etc changed this.

Being pretty confused at this time, I tried reinstalling 2.0b7 developer (one never knows...) Lo and behold - everything works again! Can't provoke it to not find the disks... OK, then I reinstall HiJack - Boom, problem is back! Tried it with v115, v117 and v118 (as I saw Mark has released another couple of versions, I'll try it with the latest&greatest in a few minutes). I could consistently solve the problem by uploading 2.0b7 and consistently get it back by adding HiJack...

Will be back after finishing catching up on the board and testing the lastest HiJack.

/Michael