[Asterisk-Users] Re: Asterisk Crackly Bad quality

[Keith O'Brien]

Thanks. On a related note.  The problem that I am troubleshooting has to do
with an IAX connection to TELIAX.   Outgoing calls are perfect.  When I have
incoming calls they are very crackly and break up.   I have checked the
jitter buffer and it is not overrunning so it doesn't appear to be a jitter
or packet loss problem.

I am beginning to suspect that since I don't have a ZAPtel card in my
machine, * is losing sync with the incoming stream.  From what I understand,
if there isn't a zap timing source * uses the incoming data stream to derive
timing.  

Since the incoming stream is using VAD, my assumption is that it is losing
the timing during the pauses in the speech.   Does anyone know of a way to
just turn off VAD in *?   This would have multiple benefits (if you have the
bandwidth).   Turning off VAD will improve voice quality by eliminating and
front end clipping during talk spurts and I am assuming will also minimize
the impact of not having a ZAP timing source.

Is there a way to disable VAD in *?

Thanks again.

-----Original Message-----
From: Martin List-Petersen [mailto:martin+asterisk at list-petersen.net] 
Sent: Saturday, December 18, 2004 8:20 PM
To: Keith O'Brien
Cc: asterisk-users at lists.digium.com
Subject: Re: [Asterisk-Users] Re: Asterisk Crackly Bad quality

Citat Keith O'Brien <keitheobrien at yahoo.com>:

> The URL you are looking for is:
> 
> http://www.voip-info.org/wiki-Asterisk+timer
> 
> Thanks.  After reading through the notes I checked my server (Dell 1750)
> and
> noted that it uses a USB OHCI interface so the first option doesn't appear
> to be an option.   Also it indicates that the second option of using
zaprtc
> <http://www.voip-info.org/wiki-Asterisk+zaprtc>  won't work on SMP
systems.
> The 1750 is a SMP system and I am running a 2.4 SMP kernel but do not
> actually have a second processor installed.   Can I still use zaprtc with
a
> SMP kernel if the second processor isn't actually installed??
> 

zaprtc should work indeed if you only have one CPU in the system.

Slán Leat,
Martin List-Petersen
Dublin, Eire
(contact info ==> http://www.marlow.dk)
--
We Klingons believe as you do -- the sick should die.  Only the strong
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