sundance-communications.com/forum Forums TDM Business Telephone Systems Samsung Telephones & Systems OS7100 IP Phone Speech Issue

I have an OS7100 MP10 V4.46e
Remote ITP-5114d V3.37 and remote SMT-W5120 both registered publicly.

All MGI/MPS port forwards done at system end.
Nothing done at either phone end.

When the 2 ip phones call each other there is no speech.
If either one calls a digital phone there is no issue.

I think this is a MPS issue, where the phones are trying to talk p2p and can't due to no port forwards in the routers for the phones.

Now in pre 4.4 i could specify that the phones could use a MGI channel, but that option is gone in 4.4.

Any ideas other then to disable MPS?

had the exact same issue on a customer supplied firewall.
All ports forwarded, even had the IT guy as a last resort forward ALL external traffic to the phone system and still didn't work. They swapped out the firewall 3 times and finally a sonicwall worked with only the required ports forwarded.
Only started happening after upgrade to 4.4x MP10a worked fine with previous 4.14k MP10.