Rhodes Chroma Polaris

ok-i just raved about getting my old polaris working with the new membrane
switch panels---
but i just noticed an odd phenomenon with the touch sensitivity---
all keys do play  fine with no touch sensitivity --and all do fine with light touch with  ENVELOPE touch ON --
but with VOLUME ENVELOPE  touch ON its very iffy--

i can get sound if I hit hard, but with light touch many keys dont play (some
do) --- at one point going up the scale it seemed evry 6th didnt play
lightly--but then sometimes two next to each other--then down keyboard it was
more erratic with sometimes 2 or 3 in a row not playing with light touch. at
first i had thought it was a bad voice--but it seems weirder than that. but the
pattern of one in 6 only worked on the way up.
i cleaned all the key contacts w/alcohol -- but that didnt fix it.
the one out of 6 pattern just doesnt seem constant now, but was certainly the
case at first.
any ideas? its just with VOLUME touch on