No voice on internal transfer

Hi

Im having a problem with voice on an internal transfer. I am running Asterisk 1.4.35 and have the server setup with 2 separate networks on eth0 192.168.5.0 and eth1 192.168.2.0 ranges. I have Snom phones on eth1 and Spectralink 8002’s on eth0 running on a Trapeze wireless network. When we call from Snom (A) to Snom (B) and transfer to the Spectralink © the call goes through but there is no voice. When transferring between Snom phone there is no problem.

I thought it may be a NAT issue but this typically will have a 1 way voice problem where here we have both ways with no Voice.

What I find strange is that we have a SIP gateway trunk where telco calls enter and if a call comes from the trunk and is transferred in the same fashion to the Spectralink phones there is no problem so the problem seems to be isolated to the local extensions across the 2 networks.

Any assistance would be appreciated

Thanks
Doug