[Asterisk-Users] No voice call from H.323-phone to SIP-phone

[shong ching]

Hi lists,

I am trying to connect SIP Phone and H323 Phone. I can call to from
SIP-Phone to H323 with clear voice. But I can't hear the voice calling from
H323-phone to SIP-phone. The ring and hookup function is OK. I am using
chan_h323 driver. I also tried changing codecs, g711u and g723.1. The result
is same.
My phones are no branded Taiwanese.
I installed pwlib 1.5.0, openh323 1.12.0. H.323-phone is fastconnect mode.
NetMeeting works both call. It's not using fastconnect mode.
Could I have some suggestions?

Regards,
Shong Ching