Hi,
I've tried both Phoner and PhonerLite for ip-to-ip calls between Phoner/PhonerLite and a softphone written by our company.

The problem is: 

With Phoner I can hear the other side only after a few seconds, although when I record the incoming audio, I can hear what I'm supposed to hear when I'm playing the recorded wave file.

With PhonerLite, according to the statistics window, most of the times nothing is received by PhonerLite, although in wireshark I see that RTP packets are sent to it. After a while PhonerLite hangs up the connection with error code 562.

Maybe Phoner and PhonerLite expect something additional except for SIP and RTP? Can they work without RTCP?

Thanks

First of all, thank you for the quick answer!
Both endpoints are located in the same LAN.
I think I'm using the latest versions, because I've downloaded them in the recent few days.
Can these problems be cause by another reason, except for NAT?

Thanks

I sent the wireshark trace to info@phoner.de
I hope this is the e-mail you meant, tell me if you meant another email.

Thanks