[Asterisk-Users] Rough Two Days

[Andrew Kohlsmith]

On Tuesday 14 February 2006 10:56, Sean Cook wrote:
> we had originally purchased a tdm2400 with echo cancellation but
> couldn't fit it in the chassis.
>
> Spent 3 - 4 hours tracking down the source of the echo to no avail,
> enabled mark2 echo cancel and aggressive echo cancel to get the system
> to where the customer was satisfied with the performance.

If you have the echo cancellation hardware then the choice of canceller has 
*zero* effect on the echo cancellation UNLESS you disable VPM support.  If 
VPM support is enabled (default) and detected, then the echocancel=yes 
enables the hardware echo cancellation.  The software echo canceller is not 
used, and all the options of choice of cancellation algorithm and agressive 
options do nothing in this case.

> Came back to the lab, pulled out a duplicate system, had the same
> problem.  So I swapped out the Digium card with an OpenSwitch6, all of
> my problems went away!  No echo, great call volumes and better yet, I
> picked up the ability to swap the ports from FXS to FXO. I will admit
> there was some difficulty with the vpb drivers as some things have
> changed in the >2.6.11 kernel that cause it to fail, but Voicetronix
> support was GREAT!  I am extremely pleased with this hardware and it
> integrated into AMP with almost no effort.

You don't specifically mention it, but did you contact Digium support 
throughout any of this?  Offhand, what is the pricing like between the 
TDM2400E and the OpenSwitch6?

-A.