This weekend I had a problem with my timers firing at odd times, I re-downloaded the timers and macros, and they still mis-fired, so I checked my hardware configuration and realized my back-up batteries had no juice left in them.
nklght: I moved this part of your post from the
AHP COMMENTS/IDEAS/FIXES section because I found it interesting and didn't want to go OT in that thread.
Outside of an On/Off digital input to the CM15A's micro-controller which supplies the battery good/bad information in the Hardware Configuration window, the back-up battery is electrically isolated from the rest of the CM15's circuitry when the unit is plugged in.
I am surprised that the battery state can effect timers as long as the CM15A does not lose AC power. Unless that digital battery state input can somehow alter timers I think your battery being low was coincidental. You probably had a loss of AC which would have caused the CM15A's internal clock to lose time without the support of good back-up batteries.
Some run their CM15A without batteries and I don't recall anyone having an issue with timers because of that.