I have two phones that I’ve been comparing (different manufacturers).
To debug call quality issues on one of them, I’ve been using calls from the phone to our main DID, so 3 SIP sessions exist (phone <> asterisk then asterisk <> provider, and the provider<>asterisk for the DID).
The “bad” phone shows roughly twice the number of packets on the phone<>asterisk session as on the other two sessions.
The “good” phone shows roughly equal packet counts on each of the 3
I’ve used asterisk server MTUs of 1440 and 1500, but it makes no difference.
Is this double-packet-count a clue, a problem, or a red herring?
The packet counts are shown using “sip show channelstats”.