Q.: Message waiting light ... how? [telecom]

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

--
Avant de repondre, jeter la poubelle, SVP.
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