No VOIP access

[MattBar_2346481]

I have a VOIP phone which I have used successfully with a Three SIM in an unlocked router. I've recently switched to Smarty on a recommendation but found that VOIP traffic appears to be blocked. The phone never registers correctly.

With 3 and EE sims, I have no issues. I have a data-only plan and I'm aware that routers may not be "officially" supported, but is this a global thing with the network or something that I may have to look at locally?

The config of the router (ZTE MC801A) hasn't changed apart from the APN settings, but I get nothing from VOIP access.

[BrianMcBriany]

I don’t have an answer for you but just wanted to make a few points:

- The access provided via the SIM allows for tethering and I personally know one or two people also using them as a general internet access (4G/5G backup) in their router (Draytek). If there’s some sort of block in place preventing VOIP traffic, I feel that should be clear/presented up front on sign up. If they are blocking, does it fall foul of net neutrality guidance/regs?

- Could there be an issue with temporarily issued IP/cgnat addressing? Might be worth some googling.

- Could there be a router setting to be changed? I know my Orbi setup has a few VOIP options to play with.