Has anyone had any joy with getting an Intertel 5000 working in Hong Kong?

The trunks are T1. I can receive calls but cannot hear anything whedialling out not even a ringtone. The phone rings the other end but when answered the caller can't hear anything either.

I believe the trunk standard to be ITU.

The service provider here says he receives my call at the exchange but gets no E & M signal from the Intertel which I pressume is why I get no audio.