Problem with Comtrend CT-600 VoIP IAD (SIP Device)-No voice


#1

I have a Comtrend CT-600 VoIP IAD (SIP Device) succeccfully working in my LAN in the office. But now i have connected it via ADSL connection and it is successfully registered with my Asterisk and able to ring each other. But when i pick the receiver no voice is coming both ways. The ring-back tone could only be hear from IAD side only.

My IAD supports PCMA,PCMU and G.729 codecs. I have purchased G.729 codec because of it’s law bandwidth requirement, but even it doesn’t solve this problem. So I think there shouldnt be a problem with the codec, but some wrong configuration in my Asterisk.

My Asterisk SVR is in the LAN and it is mapped to a public address by configuring a Static NAT in the Cisco 805 router.

My sip.conf has the following lines. Please someone help!!!

[general]

context=sip_tute ;My Default context for incoming calls
port=5060

bindaddr=0.0.0.0 ; IP address to bind to (0.0.0.0 binds to all)
srvlookup=yes
;When Asterisk is in behind a NAT

externip = xx.xx.xx.xx. ;//Our router’s serial interface
; Address that we’re going to put in outbound SIP messages

localnet=172.22.4.0/255.255.255.0

[adslrouter]
type=friend
username=adslrouter
secret=adslrouter123
host=dynamic
context=sip_tute

nat=yes

canreinvite=no
dtmfmode=rfc2833

;Qualify=yes

disallow=all
allow=ulaw
allow=alaw
allow=g729


#2

Could anyone please HELP me to solve this!!!