I'm using XP with all the latest patches with almost no other applications running on it. I first had the latest AHP, but moved to 3.228 as recommended here.
Every 48 hours or so, AHP cannot communicate with the CM15A. I've replaced the CM15A batteries, flashed its memory, etc. After much trial and error, I've discovered that X10nets.exe (service running in the background) is the culprit. It seems to have memory leaks that ultimately bring AHP useless. To get around it, I have to exit AHP, unload x10nets.exe through Task Manager and start AHP again. That temporarily fixes it for about 48 more hours. Starting and restarting AHP doesn't fix it. The service must be unloaded.
Since the OP mentioned that the "latest" seemed to have fixed his problem, I was trying to figure out which version it was to see whether X10 might have done something between when I got my system (jan 09) to now. Unfortunately, I cannot run the version I was given because of its total instability.