Seeing that I could not register for VoLTE on the Italian Vodafone network, I tried to check the availability of such service for all mobile providers in Italy. The results I found are as follows.
Vodafone: VoLTE is available, but no Sony device is in the list of supported terminals.
WindTRE: VoLTE is available, but the only Sony device supported is the Xperia 5 II.
TIM: VoLTE is available, but I could not find a list of supported devices. However, its low-cost brand Kena Mobile does provide such a list, where no Sony device is listed.
Iliad: VoLTE is currently not available at all.
Anybody who has more accurate or updated information is welcome to provide further information for Italian users.
Of course there’s no guarantee that the provider would accept an IMS connection from these devices, but any of those could work in theory. Vodaphone also has a config called mcfg_sw/generic/EU/Vodafone/NONIMS/Italy/mcfg_sw.mbn, so I guess some SIMs might not support it. The only way to know for sure is to test.
You can find all this stuff in /vendor/firmware_mnt/image/modem_pr/mcfg/configs/.
Tested and not working for Vodafone. I just switched SIM with my Android backup, which runs on WindTRE, and registration does not happen either.
This is one of those little stupid things which take little to do but make the difference between a developed country and an underdeveloped one.
I’m on French Orange, and actually had to cancel my multi-sim package for IMS to register - you can’t have voice on your second SIM. I guess there must be some configuration that works because the config is there, but it could be some obscure or premium package. Is H3G related to WindTRE, or something different? Because I think the only hopes are TIM and whatever H3G is.
H3G was TRE which has now merged into WindTRE. But Vodafone itself, my main provider, works in Germany but not in Italy.
Vodafone has disabled 3G years ago in Italy, therefore I expect VoLTE has been enabled by default where possible.
I expect that the providers have simply not implemented compatibility with Xperia devices, or possibly even simply reject registration because the device is not in their whitelist which they fail to update.
One glimmer of hope could be how it can sometimes take a few days for registration to start working. Or sometimes you need to replace your SIM. But I can totally believe everything you just said.
For what can be trusted, I contacted customer services of Vodafone and Iliad. The former pointed me to the list of supported devices (which I had already reviewed on my own), the latter confirmed that VoLTE is not yet available.
I thought about SIM replacement, although this is not listed as a requirement to work. 4G mobile data are working fine.
I’m not sure bug reports is the good category knowing there is a wiki listing all working and non-working providers. @jameson do you agree I change the category to General?
However, I defer to your better judgement here @pherjung. If you think this is more appropriate in the General category, then we should go with that (the important thing for me is to have a place for the topic to be discussed).
Well, because VoLTE is a beta version and there is a wiki I thought the best category should be General. But actually, there isn’t a perfect category in this situation. As you said you created an internal bug report, it’s logical to keep the same category here and tag as fix once it’s solved.
@flypig I let you add the tag tracked once the internal bug is created.
[on android] Perhaps see if VoWiFi works (without being on the whitelist)?
I can’t say if you will even get the option in Android without VoLTE, or if it is even available on Vodaphone. (they do have VoLTE , but don’t have VoWiFi here).