I have tested both 504G and 2102 for this call progress issue. It happens that both registered successfully and work fine, but when we dial out to a mobile subscriber with a cRBT service, we get back the call progress tone instead of the subscriber cRBT. We have tested another brand IP equipment and for that brand, cRBT is played back instead of call progress tone. We are using g729a codec.
Which parameters do we need to change in order to get cRBT played back when available instead of call progress tones?