Reply to Dan:
I have a filter on the UPS that my PC is plugged into. I will swap it out for another in case it is defective. The UPS and CM15A are on different circuits but are on the same circuit breaker phase. My AHP network has run flawlessly since I upgraded to it when it was first introduced (I have been on x10 for many years, three different homes), until a few months ago when the early triggers began.
Reply to PConroy:
The PC clock is not drifting.
All but one CM15A has been purchased from X10, one was purchased from TheHomeAutomationStore.
Reply to Bill & Noam:
Noam is correct in that the timers shift in only one direction, more and more each day.
I did, however, delete all timers using security, dusk, or dawn shifting during this troubleshooting phase in order to eliminate those time shifting variables.
What I have observed so far is that whatever noise that may be on the powerline is only impacting the CM15A clock. All timers and RF macros are being triggered and there are no phantom triggers occurring. Each time I boot up the connected PC, it does in fact reset the CM15A clock.
After I shut down, the first few timers will trigger as programmed and then each one after that will trigger earlier and earlier. What could be generating just enough noise to impact the clock only? One would think that that would take a great deal of noise.
Anyway, even though this is a new install of the AHP software, I'm going to install the software on another PC and start out fresh just to see what happens.