[Asterisk-Users] Echo after upgrade * 1.05 -> 1.06

[Florian Overkamp]

Remco, 

> -----Original Message-----
> I have a strange echo problem. Two days ago I setup * 1.0.6. 
> at a friend 
> of mine. Just an * server and for outbound calls wengo.fr was used to 
> place calls via sip. He had a strange echo on the line I didn't 
> experience on my setup.
> 
> Today I upgraded my asterisk 1.0.5 to 1.0.6 and suddenly I 
> have an echo 
> too on sip calls thru wengo!!

Can you identify which side of the conversation hears the echo ? As you
know, echo is heard on the side opposite of where it is generated.

Also it is good to have an idea of the audio path you are looking at. In
general there can be no audio leakage in a digital path, so everything that
is using VoIP cannot introduce an echo.

> I already verified wengo was not the source of the problems 
> by switching 
> accounts on the server so I'm pretty sure the problem appeared after 
> installing astreisk 1.0.6.

You could verify that by rolling back to 1.0.5 now. To be honest, I doubt
that the asterisk version will introduce an new echo issue. There are a few
things you might consider:

- The methods in which asterisk cancels echo may have been changed between
1.0.5 and 1.0.6. You would never notice this, because your setup is all VoIP
(no Zap)
- You might experience echo because the length of the audio path is now
exceeding 25 ms where it was not before. I doubt this is the case because
almost any VoIP setup will exceed that boundary. You might try to verify it
though.

> Both setups are similar, an * box with SIP phones 
> (Grandstream and Sipura 
> SPA-2000's) and a wengo sip account to place calls.

I can imagine the Grandstream or a cheap phone on the Sipura might introduce
some accoustic echo (i.e. sound that is played out the speaker and then
picked up on the microphone). In that case you would probably have noticed
it with 1.0.5. too, but maybe you changed some gain settings in the mean
time ? Also note that in this scenario the other party (behind the Wengo
network) would hear the echo, not you. There are some ways to suppress this
kind of echo, but the only real solution for this is lowering the volume on
your phones.

If this does not help, roll back to your previous version, test again. Also
inquire at Wengo if they have changed anything on their setups recently that
might cause such an effect.

Best regards,
Florian