Start here http://www.voip-info.org/wiki/view/Causes+of+Echo and follow the various links on that page. There is some really good information there on echo and what can be done.
We have had quite good success with #define ECHO_CAN_MG2 in the newest version of Zaptel (1.2.4). -- John Lange OpenIT ltd. www.Open-IT.ca (204) 885 0872 VoIP, Web services, Linux Consulting, Server Co-Location On Thu, 2006-03-23 at 10:14 -0500, Ian Service wrote: > I'm having some echo issues on a couple of lines and I'm pretty sure > it's a question of tuning the card or picking echo cancellers, I would > just like some thoughts from someone who's done it sucessfully. I've > fiddled with the echo training stuff and can't seem to get rid of the > echo. I've tried adjusting the gain to a happy level, but I'm still > left with the client side (not the callers) hearing echo. I've read > about this 1004hz 0db test number, but haven't been able to track one > down for Bell. The lines are really long (too long for DSL, so over > 7km at least) and in the country, so they're probably not that great, > and that could have something to do with it. Either that or the echo > canceller that I've picked (whatever the default in the source is) > isn't working for me. > > Has anyone used this hardware with analog lines with sucess? Any > tips/tricks you can provide would be awesome. > > I ran the fxotune program, but I really don't understand what it > acutally does, it seems to have had no effect and each line > in /etc/fxotune.conf is exactly the same... #=8,0,0,0,0,0,0,0,0 > > - Ian
