My post was too vague on surface mounted parts. The later lamp and appliance modules where a surface mounted controller IC and discrete parts.
Was the controller IC a surface mounted part?
I don't think so. Looks to me like it's a standard chip which has leads that are soldered to the board.
Also, a new development: I had one of the bad chime modules plugged in next near a lamp module. Just for testing purposes, I had the chime module on the same code as the lamp. It wasn't working, so I just left it there. Hours later, my wife came in the room and used a PalmPad to turn on the lamp and suddenly the chime went off and made her jump out of her skin.
So, the chime module started working again and was working last night and this morning. When I unplugged it and moved it to another spot, it stopped working again. Seems as thought there might be a loose connection somewhere. I'm going to experiment with it some more to see if I can find out where the problem is.