How to remove a trafficmaster tm device?

[Sprech]

There was a trafficmaster installed in my Passat when I bought it. I removed it by opening the dash board, cut the wire, done. Or so I thought.

There is a "Tm" button in the center console, and my wife the other day claimed she could hear a call being made to a call centre. There was a human being heard on the remote end. So something is still hooked up to the radio. Perhaps it's time to knock this on it's head and completely remove the thing.

I don't have the device I removed, but it's similar to this one:
Screen Shot 2015-03-27 at 14.28.22.jpg

Any advise on how to remove this completely would be greatly appreciated.

[Flash2]

I've never actually seen one of these (what's behind the dash, anyway), but I'd imagine it's just fitted like a phone kit that links into the radio via an adapter cable.
I'd try pulling the radio out and see what's behind it. If you find an adapter lead between the dash wiring loom and the radio, just disconnect the adapter and plug the dash wiring loom directly into the radio. That would disconnect the power supply to the trafficmaster control box, completely disabling it.

Jim.