For about a year, now, sporadically, our little ILEC-supplied, stand-alone, Caller-ID box has taken to flashing an amber "Message Waiting" light after an unanswered inbound call has stopped ringing. Rarely -- maybe once or twice a month. More usually it turns on a steady, green, "New Caller-ID info" light instead. (Same LED lamp for both lights -- a 2-color device.)
We have no ILEC-supplied voice mail, so there's no actual message awaiting us. And going off-hook long enough to hear 5-10 seconds worth of dial tone is enough to make that "Message Waiting" lamp turn off.
So, my question is: what sorts of signal on the line might be causing that lamp to light? or to extinguish?
TIA for any known facts.
Cheers,
tlvp