Hi guys,
Thanks for all the comments.
I have been thru all the operator type settings in the phone as described in the ukvoipforums thread and that did not help.
Testing with the phone, I've been using an adapter cable. Testing with the modem, I've been using straight RJ11-RJ11 cable.
It's an OBI200 so there's only the one phone port to play with.
If it was just the phone not working I might accept that, but it's ~6 month old modem too. Both had CLI working fine on BT POTS line. And both work ok for calls too, it's just the CLI that is not working.
I was kind of hoping that someone from OBI might notice this thread, and the 6 week open ticket, and might take some interest.