There have been numerous reports of modules switching by themselves. While this is not something we normally experience here, it did happen twice tonight.
I was in my workshop kitting, and had the ceiling CFLs on. Normally if I work in there at night I only have the bench incandescent on. While counting out capacitors, I heard the appliance module that I use for XTB testing switch twice over a period of about an hour. That has never happened before. The only difference tonight was that I had the noisemaker CFLs on, and they share the same circuit with that X10 appliance module.
Previously I had reported that the noise from those CFLs could prevent that appliance module from properly decoding commands. Here are two cases where that noise either simulated P1 ON and P1 OFF commands directly, or morphed other X10 commands being sent over the powerline into them.
So, if you have X10 modules that seem to have a mind of their own, check for any strong noise sources on that circuit.
Jeff