Sorry to bring up the dead, but Bill, were you able to ever figure out this issue?
It rained last week and since then, my key fob has been doing the same thing. I can rule out the fob itself, as it works sporadically! Sometimes it unlocks, sometimes, I have to manually open it and set off the alarm.
I replaced the battery in the fob just two days ago, and it hasn't alleviated the problem at all. Doors all lock just fine from inside, but trying to use the remote gives varying results. It either works, or it just doesn't.