[Asterisk-Users] CAPI noise and scratches - strange behavior

[Costa Tsaousis]

Hi all,

Here are some additional info & findings:

My system is dual PIII 933MHz, with a Gigabyte GA-6VXDC7 mobo.
Asterisk produces noises and scratches when the system is IDLE and
*BOTH* CAPI channels are active (with one CAPI channel everything is
fine always).
When the system is busy (CPUs at 100%), sound is perfect with *BOTH*
CAPI channels active.

Here is how I can reproduce the problem:

If I keep one of my CPUs busy while both CAPI channels are active, the
noises stop. Just a scratch here and there.
I keep the CPU busy with this:

# while [ 1 = 1 ]; do echo " " >/dev/null; done

If I run this twice (to keep busy both CPUs), then the noises appear
just every a few seconds.

I can reproduce this every single time.

Note that I have a TDM40B (4xFXS) Digium card installed that is supposed
to provide a high resolution timer to asterisk. The effect is the same
with this card enabled and disabled.

I know the easy workaround: Run setiathome permanently :-)
However, it seems that chan_capi has some timing problems...

Any help?

Costa

On Τετ, 2004-02-11 at 14:08, Costa Tsaousis wrote:
> Hi,
> 
> When I have two concurrent CAPI calls, * produces a lot of noises and
> scratches on both CAPI channels.
> 
> I am using SIP phones; it appears on all phones, even if two separate SIP
> devices are connected to the two CAPI channels.
> 
> The problem does not appear with any number of concurrent calls using SIP
> end-to-end (with * as a media gateway).
> 
> I am using FritzCard! DSL (the ISDN part of it) and kernel 2.4.24 vanilla.
> 
> Any help is appreciated.
> 
> Costa
>