Call Center Staff Can not hear incoming calls

[wildanfarani]

Dear all,
I have a problem with my 3CX Phone System 11 that my call center staff can not hear caller voice if there is more than one incoming call at the same time.
First incoming call works fine, but if there is second call, my staff can not hear caller voice but the caller heard normal

My 3cx sitting in LAN, we have tried to put our 3cx server in DMZ so it can get public IP but our vendor had trouble to setup the system. this is my simple network diagram:

Any ideas?

 

[Kevin Attard Compagno]

@wildanfarani

Try adjusting some of your extensions to:

PBX Delivers Audio = ENABLED
Supports ReINVITEs = DISABLED
Support Replaces = DISABLED

...does that change things?

 

[wildanfarani]

@wildanfarani

Try adjusting some of your extensions to:

PBX Delivers Audio = ENABLED
Supports ReINVITEs = DISABLED
Support Replaces = DISABLED

...does that change things?

No it doesn't...Second caller can not hear operator voice, First caller heard normal..do you have another solution?

 

[3397premier]

Have you tried verifying the ports you have open? I'm sure you know this but make sure you have two open ports for every current call.

Has it worked previously or is this a new setup? If it had worked previously what have you changed on the phone server or network?

 

[Kevin Attard Compagno]

@wildanfarani

Do you have access to the 3CX Support Portal? To look at this in any more depth you would need to open a support ticket.