It's been a while, but I'm thinking the NULL referred to something in a dial string as opposed to a space in a text field, and pressing HOLD generally clears the decks in a text field.

VoIP technology and soft switches have pretty much ruined remote access via modem. Sometimes reducing bit rate works, but it can test your patience.

If you have a network connection in the room with the phone system, why not put a junk laptop with remote access software and the ADIX programmer on it, and just leave it connected to the ADIX?

Sometimes the thoughts in my head get so bored, they go for a stroll through my mouth. This is rarely a good thing.