Where exactly can I look to see the problem? I'm good at soldering and could make the repair myself.

Well, assuming it's not something silly like the perfectly-good cables pulling loose from the drive connectors (I've had that happen as well)...

Just remove the drive tray and the cabling and look at the IDE connector on the motherboard. On my Mk2, the pins that attach it to the motherboard are really obvious, they're kind of like flat tabs that go out from the connector onto pads on the motherboard. Just look and see if those seem to be properly soldered or not. If they aren't, just touch them up. It's probably a pretty obvious thing when you see it.

My unit actually had the problem to begin with and I can see that it was hand-retouched before it even got shipped to me.

I don't know what it would look like on a Mk2a, dunno if the connectors changed or anything.

To have this happen with 3 different Empegs is not what I would call "some units".

Assuming it's the same problem with all three, then yeah, I'd say you either got really bad luck of the draw, or it's a more widespread problem that we think. Although disk trouble can come in many forms, so you might not really be having the same exact problem on all three units.

If any of your units happen to have this problem, I'd actually be really interested in getting some clear, sharp digital camera photos of what it looks like before the fix is applied, so that I could put it in the FAQ.