i want to use G.722 with its wide audio bandwith of 7kHz. But i have found that FreeSwitch resamples always from 16000 to 8000 Samples/s if i connect a "standard device", i. e. a SIP device with a "G722:9/8000" in its SDP.
On the other side it is possible to use full bandwith if there is a "G722:9/16000" in SDP.
I think this is not correct! FreeSwitch should always use 16000S/s and also use "G722:9/8000" in SDP!
Read RFC3551, 4.5.2: ...Even though the actual sampling rate for G.722 audio is 16,000 Hz, the RTP clock rate for the G722 payload format is 8,000 Hz because that value was erroneously assigned in RFC 1890 and must remain unchanged for backward compatibility. ...
You won't get any argument from me on this. We do advertise G722/8000 and G722/16000 but in all reality G722/16000 should be moved up to the dynamic range. /b