[Asterisk-Users] Re: TDM400P digium card

[Alan Ferrency]

 "Nora Lavelle" <nora at silverspringnet.com> wrote:

> Thanks dewey. Any feedback on how to debug this issue ?

Regarding sound quality issues with Sipura SPA-841 phones and Asterisk,
please check out this page I created on the voip-info Wiki:

http://www.voip-info.org/wiki/view/Asterisk+SPA-841+Sound+Quality

Specifically, if you have not set the SPA-841's "RTP packet size" and
"Silence Suppression" parameters correctly, then you _will_ have sound
quality issues.

After that: Are your phones sharing the same network segments as your
non-VoIP ethernet data? Do you have a lot of ethernet traffic? We found
that even on a fully switched network, if the SPA-841's received
excessive ARP traffic (which is broadcast to all switch segments, even
though most other network packets are suppressed), we had periodic
"robot voice" sound issues.

Check this out, and see if it helps.

Thanks!

Alan Ferrency
pair Networks, Inc.
alan at pair.com