[Asterisk-Users] Echo on a PRI

[Andrew Kohlsmith]

On Tuesday 20 July 2004 09:04, Troy Settle wrote:
> On the subject of echo on a PRI, I too get this, but only when calling
> people in certain rate centers.  Calls within my LATA (primarily VZ) are
> completely free of echo.  Calls to a neighboring LATA (all Sprint) have
> echo on almost every rate center.
>
> I wish I knew more about this so I could rip Sprint a new one and tell them
> to fix their trunking, but...

Are you sure it's Sprint's fault?  I mean perhaps calling within your own LATA 
has less delay than calling neighbour LATAs and, combined with the delay that 
the T100P/TE405P introduces, presents enough delay to perceive echo...  

IME It's not a telco problem.  I also have echo when calling certain numbers, 
both within and outside of my own LATA  (at least I think it is) ...  My 
conclusion is that *s echo cancellation is very hardware-specific, but with 
echotraining=800 it's good enough for what we use it for.  

The only problem with echotraining=yes is the 8/10s delay before audio is 
heard -- sometimes the start of conversations is cut off since our 
receptionist doesn't have to life a receiver from the cradle to her ear.

-A.