asterisk users - Jan 2005 - IAX2 bridging = one way audio

Our * box is behind NAT with 4569 forwarded to it. I'm using stable 1-0
version. We're pure VoIP. Our SIP phones can use * to dial out, and can
receive incoming calls, and conference in another SIP. However, if we try
to conference 2 IAX connections together, we'll get one-way audio for one
of the connected IAX devices. I found that this also happens if I use an
IAXy to call out from * (outbound calls get bridged with teliax.com). The
called party receives no audio, although I can hear them.

Here's my iax.conf [general] secion. Should I change the bindaddr? I
thought 0.0.0.0 just listened to everything, so that's why it did that.

[general]
port=4569
bindaddr=0.0.0.0
disallow=all
allow=ulaw
allow=alaw
allow=gsm
allow=g729
allow=g726
iaxcompat=yes
bandwidth=high
jitterbuffer=yes
dropcount=3
maxjitterbuffer=500
maxexcessbuffer=300
tos=0x18
register => XXX:XXX@voip.teliax.com

IAX2 debug shows so much info I don't know where to start. I don't see
any
errors or warnings in the console though.

TIA,
-Ron