Your configuration is fine. There is no way you can go on the same chanel when you are using T1 PRI cause all chanels controled by D-Chanel. The only things I can think of that either your tech made a mistake in programming for PRI or he is right and you are having a problems with your carrier cause of both way communication problems. One person cann't hear another. I would call carrier and ask them to open a trouble ticket to check out a Loop.