Been a while, hope everyone here is well. This post is going to be rather technical so it's best I break it down a bit.
* Raspberry Pi 4 4GB running Freepbx
* Quectel 4G modem for calls / data (as fallback)
* Sipgate "Basic" Starter landline
* Yeastar TA100 for Analogue to SIP
* Virgin Mobile SIM that appears to roam on Vodafone
* Sky Mobile SIM On VM02 (as test sim)
* To make life a bit easier I've configured PJSIP to use Sipgate's STUN server
Now onto the issues:
It would appear (unless I'm going crazy) that Vodafone are hindering VOIP calls not going through themselves. Sipgate will register fine & stay online but NO audio in/out. No matter what I do.
I assumed it was some sort of configuration issue at first, but I've already broken everything down! However the EXACT same configuration when using the Sky SIM works perfectly fine. I only swap the SIMs over and it all works great.
The Freepbx logs for both SIMs are identical as far as Asterisk is concerned the calls are connected but there is absolutely no audio when using the VM on Vodafone SIM. With/without the STUN server, and I've tried a few!
I know what you're going to say, just use the Sky VM02 SIM and honestly it looks like I will have to but for Vodafone to mangle SIP like this is absolutely disgusting but in no way surprising. Mobile calls and data otherwise are fine.