in germany there’s a concept named “call by call” which means that your calls get routed through another provider for cheaper rates by using a calling prefix. (Example: 01067-destination-number) This is especially interesting for calling to mobile networks or international numbers.
These providers do announce the current rate they charge at the beginning of the call, before it starts ringing he destination phone. For some reason, freepbx suppresses this announcement and instead plays the calling tone.
Interestingly, the providers announcement can be listened to in the recordings.
Any tips on how to fix this, so the user can hear the announcement?
The issue here is that this specific provider does only signal 180 Ringing (not 183 Session Progress), which therefore leads to the phone not opening the media channel. Instead the phone plays local ringback.
Can anyone confirm that this is non-standards compliant by the provider?
I was able to mitigate this by setting inband_progress=yes manually for all my extensions in pjsip.endpoint_custom_post.conf like this:
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inband_progress=yes
This forces asterisk to always send 183 Session Progress even if it didn’t receive that from the provider, which in turn, leads to the local phone opening the media channel.
Setting it on the trunk doesn’t help, and unfortunately it is not possible to set it for extensions through freepbx.
Is there anyway to set this automatically for all extensions?
