Meetme with delay on one direction

Hi All!

I have a meetme-server (web-meetme with cbmysql) running with ztdummypll and with a E1-Digium-Card.

When I dial in via 2 SIP-Phones (SNOM 320) to one Conference-Room and keep the room open for around 1hour then I have on one direction a delay of 0,5 seconds, but on the other direction no delay.

And there is no difference if I am using ztdummy or the hardware-card.

By the way, I am using an AMD Opteron DualCore DualProcessor but with 32bit Software (with 64bit it was not useable - the delay was to big).

Any Ideas why I have the delay just on one direction?