Demonic Power Door Locks

We have a 2003 Toyota Avalon. Great car, but occasionally, while driving, the power door locks actuate (unlock) by themselves. This anomaly occurs more often on warm and humid days. This has been an issue for 6 years. We took it to the dealer three times, but they could not duplicate or repair the problem. Have you ever heard of this? It doesn’t seem to have anything to do with the key FOB.

I suspect the door lock switch has some dirty contacts inside it.