Forward to cell phone is silent

I have incoming calls ring my extension first, then dial my cell phone if I don’t answer. This all works great except that when I answer my cell phone, there is no sound in either direction. I can see in the * CLI that it bridged the calls, and both * and my cell phone say “connected” but no sound.

can you call directly from an internal extension to your cell phone and get audio? if not, can you call from an internal extension to anywhere in the outside world and get audio?

if not, problem lies between asterisk and your outbound gateway (which may be a PCI card in same chassis or another voip GW elsewhere). problem could be codec mismatch (less likely or SIP call setup would fail, assuming you’re using SIP), or could be firewall/nat issues between asterisk and gateway, or could just be other config issue of some sort.

if other calls ok, then maybe you have an external gateway and asterisk is hairpinning calls back from whence they came? maybe your gateway isn’t happy hairpinning calls back out the PSTN/TDM side of things?

more data is needed to isolate this issue.