Do you mean that it resets its filenames or do you mean its shutter activations (or something else that I cannot figure)?
OK, I'm realizing that frame counter is probably a video thing (I never do video). But I'm wondering if your seemingly random resets is related to a kind-of similar problem I had with filenaming. It involves the use of Custom modes. Here is what I posted on the other m43 forum:
I think that using Custom Modes was in fact the problem. Basically, what seems to happen is: say you have your camera set to use standard filenames. Then you set Custom Mode 1 to do say HHHR. So you start getting regular filenames on your HHHR shots. You then later set your camera to use special filenaming, say beginning with OM (as I did). Well, that apparently does NOT ripple thru and change the settings stored for Custom Mode 1 (for HHHR in this example). So when you use C-mode-1 you revert to the standard names. When you turn the dial to regular shooting, you are back to getting the special naming.
In that case I was getting what looked like random filenames, some starting with "OM" when I was in regular mode, and some starting with the default naming whenever I switched to Custom Mode 1. It can appear to be totally random, for sure.
Maybe this is what is happening with your frame counter? Custom Modes retain EVERYTHING, it seems, so if you make some important camera-wide setting (like how it assigns filenames), you need to reestablish (redo) all your Custom Modes or you will revert to whatever was set earlier every time you use one.
This might not account for your problem, of course, but it sounds like it might.