[Freeswitch-users] FreeSWITCH port audio module

[Jason White]

One of the valuable features of FreeSWITCH is that it can be used as a soft
phone, as described on the wiki. In testing this, I discovered the following
issues, any comments on which would be welcome.

1. FreeSWITCH>pa rescan
-ERR no reply

FreeSWITCH>

After plugging in a USB head set and running this command, the new device
wasn't enumerated by pa devlist. Restarting FreeSWITCH of course solved it,
however.

2. More seriously, when using port audio (with a head set as the audio device,
in case that's significant), I'm hearing digital distortion (clipped samples?)
when the other party speaks slightly more loudly than usual. 

When calling via a Snom phone (rather than PortAudio) I have only experienced
this distortion when using FreeSWITCH under G.722, but I'll have to do more
testing to identify the exact combinations that produce it and those which
don't. I haven't heard it with an 8khz call from a SIP phone, so it does
appear to be a FreeSWITCH issue to some extent. I haven't been able to
eliminate it by adjusting the Alsa settings of my audio device.

3. I've encountered errors while trying to access an Intel HDA sound card with
FreeSWITCH, whereby PortAudio fails to open the audio device. Setting the
sample rate in portaudio.conf.xml to 48 khz may have contributed to the
solution, but there have been other changes to my system as well (including a
FreeSWITCh upgrade to revision 10889.

Some sound cards only suport 48 khz, apparently, so if others have problems, I
would suggest adjusting the sample rate in the configuration as I did.