I have about 15 or so PD5WS RF switches. I have installed the MLC on all of them. When I returned from a trip recently I noticed that on at least 10 of these devices the front LED was flashing red. All of my other devices were OK.....about 90 dimmers and pico remotes. First time I have seen that...to clear it I just cycled the switch ON/OFF once by hand and it was OK. When the LED was flashing Red, I believe I was not able to control it or get status on it. (Didn't pay much attention to that at the time.......). In any case, everything was back to normal once it was cycled OFF/OFF.
What could have caused this?