No Audio With 3CX On Iphone 4 Using AT&T 3G (WiFi Works)

[alteredstate]

Hello Everyone,

I have 3CX 1.1.5 installed on iPhone 4 and it works great except when I'm off WiFi and using AT&T's 3G network.
Here's the scenario:

• 3CX works perfect with LAN WiFi going to PBX Server.
• 3CX works perfect with offsite WiFi going through WAN to PBX Server. (e.g.: it works perfect when I'm on home WiFi and connect to the PBX server at the office)
• 3CX places call and shows connected but there is no 2-way audio when I'm on AT&T's 3G network.

I figured if 3CX works perfect on WiFi (no matter where I'm at) then it should work on 3G...unless AT&T has decided to block SIP connections; 3CX use to work on AT&T's 3G. Has anyone experienced this and could perhaps provide a solution?

 

[alteredstate]

Can anyone help me out on this issue?

 

[leejor]

at&t has, in the past, blocked a number of data services, and it appears that they still are (or plan to, unless you sign up for special data plans), so, it would not surprise me. You may want to ask them what their policy is, on VoIP.