This has to be a simple one

I recently reinstalled our Asterisk ( test machine (Ubutnu Jaunty) on the office LAN. Everything appears fine, except I get no audio from it. It is receiving DTMF tones fine.

Playback() seems to be doing something, but a tcpdump on the host shows audio only from my handset to Asterisk, nothing from Asterisk’s playback() however.

We have a second asterisk installation and that one is working fine. We are baffelled! Both are behind the same NAT/firewall and connect to Gradwell using IAX2. The test box has Asterisk/Dahdi_dummy built from source.

Must be something simple but I really need some suggestions… Thanks!

To be more precise we’ve done a ‘iax2 show channels’ during a call, and there’s hardly any Rx/Tx going on. At the end of the call the counters read Seq (Tx/Rx): 00015/00020.

You would expect these to be much higher.


I have only seen this when zaptel/dahdi is setup wrong, normally a zaptel cad is configured but not installed.

make sure that just ztdummy/dahdidummy is installed

do calls work OK between phones ?