We have a client who has 2 locations, connected by a point to point line. They had an older Samsung 500 system with an MGI card which we just replaced with a 7400 system with an OAS card. Now their 2nd locations has been totally dead in the water for 2 days now because they use VoIP phones at that location. The phones dial out ok and connect ok, but the user cannot hear anything at all. No sound. Just dead air. Nothing has changed with the line and the VoIP phones were working fine with the older system. Port forwarding in the router should not be necessary because it is on the same network due to us using a point to point MPLS line. We have turned off MPS in the system. Any suggesting would be much appreciated!

In case it matters, we are using Samsung ITP-5121D VoIP phones. Thanks again.

I would look at what ports you have open on the router

different ports are open on oas card

It may be worth turning MPS off in system options

Disabling MPS won't make a difference.

Do you have private with public set on the MP/OAS card?

is the remote site using the same IP range?

Make sure you put the Ip ranges in the Private IP list dm 5.2.8
white list also dm 5.13.10

What do you mean by ranges? I entered all the IP addresses from the remote side, still not working. Each voip phone has a static address.

ip adresses on system side are 10.133.112.172

On the remote side 10.228.134.100

MPS is turned off.
Phones ip's are white listed.
Public w/ Private.
I can see the phone in MMC 840. But it never connects.

You can turn mps back on. What andma has said above will fix it.
Also you can just enter 10.228.134.255 rather then all the individual ip addresses.

Had to change back to "Private." And the phones connected finally.
But I have no audio now.

Can you send me a database? and I'll have a look

Voip phone to Voip phone connects fine across the network, but this message shows in the screen IP conflict 2426:4206:jclc. Calls from a regular digital phone to voip phone still drop off. All this trouble is with the new OfficeServ 7400 we are trying to install. When we put the old DCS 500 system back in place everything works fine. Thanks for everyone's input so far.

Some additional info we have found out is that when we are local and make calls from a regular digital phone to voip phone things work fine. However, when we try to make a call over the point to point MPLS line from a regular digital phone to voip the OAS card reboots itself. This does not happen when we are local.

I've never seen an OAS card do that. This is the cause of your speech issues.

MGI16/64 with v1.28 software does this.

I would update your OAS card to 2.05 and the system to 4.75

Thanks for your help nameless. Upgrading the MP40 to 4.75 and updating the OAS to 2.05 cured the problem.