3rd party grip oddities??

Howdy all,

Let me start off by saying I've been using my Opteka grip on my 7D for over a year now and it functions perfectly normal. No issues with it at all. Well, I've encountered a weird phenomenon with an Opteka grip for my 60D. The grip actually belongs to a friend of mine and he was having an issue so he passed it along to me to see if I could figure out what was wonky.

The 60D with grip and no external flash = functions fine, no issues
The 60D with grip and Metz 50-1AF flash (my friend got this same phenomenon with his Promaster flash) = about 10 pictures in, the camera makes a weird noise, error message on the top LCD. Have to remove batteries to reset camera.
The 60D without grip and Metz 50-1AF flash = functions fine, no issues

When I get home I'm going to try the camera with grip and my 580exII to see what happens. The 60 firmware is up to date; Metz firmware is up to date; all connections are secure. Not sure how it all relates to each other, but the grip seems to be the common factor here.

Anyone have any thoughts of other things to try to narrow things down more? I'm thinking my friend should contact the company (it is only a few months old) and see about a replacement.

What's the error message? What's the trigger voltage of the Metz, and of the Promaster? I suppose that if the flash has a moderately high trigger voltage and the grip's not properly, well, I guess "isolated" would be the closest term I can think of (preventing reverse flow of current if the voltage supplied by the flash is much higher than that supplied by the batteries), it might act like you're seeing.

Strange thing is there is no number associate with the error. It just say err in the top LCD. As far as the trigger voltage, I can't seem to find any numbers, just sites that rate the voltage as "safe".

You'd probably have to measure the trigger voltage yourself by using the probes of a DC voltmeter to trip the flash (one probe to the center contact on the bottom, the other to the contact on the side of the slipper).

Hmm, I'll have to do that when I get home today. Even still, my Metz (and my friend's Promaster) worked fine on a 50D, 7D, 5D, etc... so it would seem weird that on the 60D (only with the grip attached) that it would act up.