I'm copying this message over from the polysix group where I just posted it. I thought someone else may want to have a go to confirm this. I am not sure if this is the 'failure mode' of ALL Mono/Poly and Polysix keybeds but it could well be. YMMV but it worked a treat for me and costs nothing.

Tonight I may have busted an important myth... I'm kind of hoping, anyway. After looking at the copper contacts on the keybed circuit board that the 'pills' make contact with, under a very good stereo microscope - I noticed there was what looked like a significant amount of what I'd call 'varnishing' where the pills had come into contact with them. This is not visible to the naked eye - unless your eyes are a hell of a lot better than mine - which is possible.I also checked the conductivity of the 'old' carbon pills and found them all to be pretty decent - somewhere in the 70 ohm range - certainly no better than i could do with 'keypad fix' or caikote 44.

So on a hunch I made a little ball of 00 grade steel wool that i held with tweezers and (through the microscope) went through and cleaned up ever copper pad so it appeared bright an shiny - WITHOUT doing any sort of reconditioning or recoating to the carbon pills themselves.

Result A full keyboard of well behaved keys!! I see no reason that it won't stay that way for a few years (depending on how the 'varnish' on the copper is created - breakdown product in the rubber pill material perhaps ).

Anyway- i thought i'd share this with you - also a nice solution because it costs NOTHING outside of an hour or your time.