Issues with Jabber calls to internal DNs over VPN

[KhanalZ]

We are having issues with Jabber calls over VPN. MRA to MRA calls has no issues but if i call from Jabber from my VPN laptop to another user's Jabber who is also using VPN, there is no audio and calls appear in the cube router. I can see a multiple instances of the same calls as shown below:
132675 ORG T18 pass-throug VOIP P 192.168.24.10:25356
132676 ORG T18 pass-throug VOIP P 192.168.24.10:5858
132679 ORG T18 pass-throug VOIP P 192.168.124.11:19532
132680 ORG T18 pass-throug VOIP P 192.168.124.11:30234
132691 ORG T18 pass-throug VOIP P 192.168.39.190:35694
132693 ORG T18 pass-throug VOIP P 192.168.39.190:35698

Since both numbers are in the internal partition in CUCM and CSS assigned to those devices has access to internal partition, this is no configuration mismatch issue. If I don't  connect to VPN and make the call, everything works just fine.

Wondering if anyone has experienced this type of issue and if so what would cause this?

Thanks,

KhanalZ

[garethpeart]

Sounds like a firewall issue to me if CSS and partitions match.

[Nithin Eluvathingal]

It appears to be a firewall issue. I had a customer with similar problems where, when they were on VPN, they couldn’t make calls—they couldn’t hear anything, no audio at all. The firewall team, after working with the firewall TAC, resolved it