I used the Leviton HCA02 about 2 years ago and learned about firestorms, as Brian mentioned, the hard way. Replaced it with a Leviton 6201 and all those problems cleared up. Now, however, for about 6 months I get erroneous signals on the line causing a variety of things to go on or off.
I've discounted noise (although I have filters everywhere except a whole-house filter) because the signals are not really totally random: they ONLY occur when something is tripped, such as a motion sensor, and very, very often it is an "11" code (B11, C11, D11, etc.) I'm monitoring the line with the AHP Activity Monitor. Sometimes it sees the error; sometimes it doesn't. I've also changed all the modules of lights that are most often affected.
I'm using a V572 transceiver with a Smarthome adaptor (also replaced the V572 with a new one and tried a new X10 adaptor with it, but got the same results). I'm suspecting the repeater is receiving a code and occasionally repeating another (which would explain why the Activity Monitor doesn't always see it since it's only looking at one 120V leg.) I'm also running out of things to change! Any thoughts would be much appreciated....
