Linux - Softphone - Audio Problem / Bad sound quality

Hi all,

I have the following problem:

I’m using 4 machines with a softphone (IAXCLient) on a Knoppix Linux.
On the * Server I have a SIP Trunk from a Phone Company.

When someone calls in (from landline), he gets into a queue and then connected to a Softphone (on the linux box)
The soundquality on the caller side is very bad (choppy).

I made some tests with other linuxes on the same machines (FC4, Suse 10, Kubuntu) always the same audio problem.
(Also exchanged the network and audio card, to make sure it is no hardware prob)

If I install a windows XP on these machines the quality is good.

Has anybody got an idea what I’m doing wrong here?


Has Anybody got an idea for me?