No sound

Hi everyone!

My problem is following: I’m using Grandstream GXV 3000 phones (all on the same LAN) with asterisk 1.4.11. The codecs on all phones are configured in the same order and enabled in sip.conf. When I make the call the phones say that they are using ULAW/H264 for communicating. On the callee phone both video and audio work great, but on the caller phone I’m not getting any sound (the video works). I tried this from different phones (all the same model with the same configuration) so I can exclude phone configuration error… What could be my problem?

THX, Dado