IP Softphone 5.1.5.5 One-Way Audio

[twix79]

We have seen some interesting behavior while using IP Softphone version 5.1.5.5 connected to CM 2.2. While connected either through the internal LAN, or our encrypted Wi-Fi, it works perfect. However, if we connect via VPN we get two-way audio when calling a TDM device (public network, voicemail, digital station), but one-way audio when calling another IP phone. We had seen some issues with having a personal firewall on the machine and using VPN, but thought we had those cleared. Has anyone else seen similar problems using VPN and IP Softphone? The signalling works fine, but the audio is not being passed correctly.

Thanks.

 

[twix79]

BTW, we are using Roadwarrior mode.

 

[twix79]

We think this is related to a firewall issue. We had defined specific machine names that could access specific subnets on our LAN. These subnets contained our C-Lans and MedPros. However, once the call is sent to another IP device, it is shuffled off of the MedPro. Once that happens, we are sending packets to a subnet that we don't have access to. So the firewall blocks it. In a TDM conversation, the audio continues to go through the MedPro where it is allowed to pass.