Customer with a 2 year old stse rev 1.01. No V.M. 3 co lines with 5 phones. He says when he is on one phone with hand set off hook, if another phone Intcm another phone the phone he is using the Intcm comes over the speaker of that phone ??
You ideas are again welcom.

Thanks Gary S.

By all rights, that is impossible Gary. Does your customer have a second phone in the room? Is it possible that the internal caller knows how to use off-hook voice over feature (628) to his extension?

If this really is being caused by an unrelated station-station call, then a system default is certainly in order. Have you actually witnessed this?

Never, ever trust the customer's description of something as obscure as this one.

this is a stretch and doesn't quite fit your description, but if it really does come over the speaker and not the handset, is he mistakingly creating a conference call and then activating group listening?