hi list!
I have one asterisk pbx connected to a PSTN via an E1.
Everything works just fine, but there’s something strange.
When I place calls to outside, via PSTN, I hear two ring back tones: one
comming from my PAP2 and one comming from the PSTN. If I put the
r option in the Dial command, I just hear the tone from the PAP2. But it is not
what I want, I want to hear just the tone from the PSTN, as it is most reliable.
I tried removing the ring back tone from the PAP2 configuration and it worked just
fine, I removed the r option and heard just the PSTN tone. But when I call to some
internal extension, I cant hear the ring back tone.
Ok, what I want to do is to cancel the ring back tone from the PAP2 just when I place calls to outside world… I’ve tried the progressinband=no, it worked like what I wanted, but there’s a very loud noide in the beggining of the ring tone, that can really hurt my ear 
. I dont know why this noise…
anyone here knows something about how to do this?
regards
Carlos Barros