OpenVox B100P and sound problems with ulaw/alaw codec

Hello,

We have an Elastix 1.6.2-7 installation (with Asterisk 1.4.33.2) working with 20 IAX extensions and an OpenVox B100P attached to it in TE mode. The system is almost working ok, but we are having some sound problems with external calls when we use the ulaw or the alaw codec on the IAX extension: on the IAX side it sounds metallic with a little of background noise . We have also tried:
1. External calls with gsm codec: working fine.
2. Internal calls between IAX extensions: working fine no matter what codec we use (even doing transcoding).
I must say that the test extensions are on the same lan without other devices and latencies of 1ms and that the card is configured with misdn.

P.S.: I've read that is not possible to use fax with misdn: maybe with dahdi??

Thanks!

hi:
the default of codecs in mISDN is alaw or ulaw, if you using IAX, you have to using alaw, ulaw, gsm or others. the codec trans coding is done by asterisk. i think you have to try in few ways:
1) try different version of asterisk.
2) set gsm as a top priority.
3) fax with mISDN will be very troublesome, you are worth trying dahdi.

Hi James,I've been trying dahdi following these instructions http://wiki.openvox.cn/index.php/OpenVox_B100P_User_Manual_for_dahdi. Dahdi is able to see the channel but asterisk isn't. Here the problem is that Elastix 1.6 comes with Asterisk 1.4 and Asterisk 1.6 is needed. A core asterisk update to 1.6 on a system like that has no sense to me, so I'm planning a reinstallation of Elastix 2.0 because it comes with Asterisk 1.6. I'll let you know about my progress :lol (of course with dahdi).

Many thanks for your time and effort!
Manuel

Hi,

I have now Elastix 2.0 (with Asterisk 1.6) with Dahdi. The fax is working ok now and the problems with ulaw/alaw codecs for calls routed through the OpenVox B100P are gone :victory:. Hope this info will be useful for someone.

Many thanks!