I started a new post just to show how sometimes it IS other things and not X10. Refer to
http://forums.x10.com/index.php?topic=22263.0 for background.
The short of it is a couple of Levitron HCM06-1D 1000W dimmers controlling outside lights would go to full bright with no known cause. I’d reset them dim and a while later, they’d be on full bright again.
After performing typical X10 troubleshooting including command monitoring, no X10 related causes were found.
I noticed a side issue - other non-X10 lights would have a very short flicker every now and then. I started keeping an eye on the dim level to confirm dim setting. Then, right after I’d see one of these very short flickers, I’d check the HCM06-1Ds and yep, full bright again.
This went on for about two weeks, but things have been operating fine for about a week. So I called the local power company today and asked them if they were doing work in my area. The answer came back as yes, they were doing relay and transformer swap-outs for about two weeks and it ended about a week ago. The very short flicker I described would be seen as they switched relay circuits. Ah-HA! Evidently, the HCM06-1Ds were susceptible to these power-line interruptions and resetting themselves to full bright.
So, I just wanted to relate another story that sometimes it IS something else, and not an X10 inherent flaw. So now I get to put the dangling HCM06-1Ds back in the wall, and take out all the dim-reset-commands every 1/2-hour as I put in my CM11A and go back to the way it was. Problem solved.