VOIP Traffic to Branch Networks drops

[kipbriann]

I have Meraki MX firewall connected to 3 branches ISR Routers over MPLS. Connectivity between the sites is up and branches are accessing all resources in HQ. However, Voice traffic is one way, Branch users can hear HQ users but not the other way. What could be the issue?

[alemabrahao]

It is most likely caused by asymmetric routing or firewall/NAT issues.Take a packet capture to validate that the wave may be at fault.

[PhilipDAth]

Are they talking to a phone system on-premise or in the cloud?

Is the MPLS network connected via a LAN port/VLAN on the MX, or via a WAN port?

[kipbriann]

The Call manager is on prem in HQ. The MPLS link is connected on LAN port. WAN port has internet breakout link for all users including branches.