Unable to hear voice on Cisco IP phone

[Vikrant Ambhore]

Hello,

I am having an issue with the Cisco 7931 IP Phone over a VPN to a UC520. I have my phone connected to my UC-520 over IPSEC VPN  and I'm getting a dial tone. When I try to contact somebody at the office using the extension the person hears the phone ring but when they answer the phone they cant hear my voice. The same thing happens when they try to reach me.

Can anyone help me

Regards

Vikrant

[somgupta244]

Hi Vikrant,

Are the ports opened on the firewall to permit RTP?

Is the issue only happening with 7931 phones or all of them?

It seems to be some issue with the way VPN is set up. I have seen numerous issues when VPN is configured.

Thanks,

Som.

[Vikrant Ambhore]

I think we should configure on remote side as per below, am I correct ?

ip access-list extended BlockIPSec2HQ
deny   udp any host A.B.C.D eq isakmp
permit ip any any

A.B.C.D = IP of Call Manager side router

[dennis916]

Hi Vikrant,

Kindly check the policies setup in you VPN, this is a usual Problem when voice traverse via VPN, one way/two way audio path issues.  Hope you could send a few information as well so we can help.  I agree with Som, check the RTP setup.

Regards,

Dennis

[Vikrant Ambhore]

Can u explain  what u said exactly, I am new in VOIP, so please suggest me how to check RTP setup