I have a similar problem with my unit but the keypad issue is not intermitent. I simply have some keys (i.e. Bake, Cancel, 5, 0) which work, and others that do not (i.e. Convect Bake, Clock, Timer, 3, 7). What is the likelihood that it's my keypad gone bad, or the stacked set of PCBs? I tried the cleaning of the ribbons as recommended, but no luck on anything new. I did get numbers off the PCB unit and have found someone with a slightly newer set of PCBs. Mine are 00n21615422 Rev A and the advertised part is 00n21615422 Rev C. My date code is 6088 and the advertised part's date code is 9028. (Are those Julian dates?) Anyhow, what's your feel as to whether it's worthwile for me to get the PCBs replaced? Thank you.