[asterisk-users] Sangoma A102 w/ EC module gets intermittent echo /audio artifacts

[Eric "ManxPower" Wieling]

Colin Anderson wrote:
> I've replaced 2XTE110 with an A102 with echo cancellation specifically to
> deal with echo problems. However, user feedback has indicated to me that on
> some calls (not a lot, but some) the call is unusable, with audio
> artifiacts, described by one user, as: "very bad phasing reverb & feedback
> (from my rock & roll days)". This is quite intermittent, as in most cases,
> the user says, it's a one-time thing, they hang up, the problem caller calls
> back, everythings good. It's as if the Sangoma is trying too hard? I
> personally have not heard this, but I have to trust what the users say. 
> 
> Some ideas I'd like to bounce:
> 
> 1. tx and rxgains - this card is plugged into an Atlas 550 which seems to
> run a little hot on the gains. 
> 2. Timing - the card takes it's sync from the Atlas, which in turn syncs
> from the PRI. Maybe have one port on the card take it's timing from the
> other port? Don't see how it would be relevant, but hey, that's all I've
> got. 
> 3. Taps? Does an A102 even care about taps or just echocancel=yes?

I have fixed similar problems by reducing the gains.  I call it "ECFO" 
Echo Cancel Freak Out.