Bug#386052: tried signalling=bri_cpe

[Cybaer]

Just some report about my weekend experiments: I tried

signalling = bri_cpe

instead of the parameter

signalling = bri_cpe_ptmp

which would be normal for a single ISDN card. And - it worked - not as
well. I could dial out but had a horrible echo on the line and a
crunching sound at dial startup. Dialin was not possible anymore.

When I switched back to signalling=bri_cpe_ptmp without restarting the
machine - only asterisk restart - dialin and dialout worked - mostly.
The echo was still there and DTMF dialing was impossible.