asterisk users - Jun 2007 - mISDN Fritz Passive Card

Hi all,

I am using mISDN with a Fritz!PCI v2.0. The card works without
problems until I use concurrently the two channels. In that moment
appears a little echo. I have reduced the tx gain but the echo not
disappear. I see in messages:

kernel: ECHOCAN: i:4000 TXBUF Overflow txbuflen:496 txcancellen:32

Some idea how resolve this problem?

Thanks,

--
Manuel