No IMS/VoLTE – o2/PremiumSIM cannot register in LTE network

/e/OS Devices Samsung
1

Hello /e/OS team,

I am using a Galaxy S9+ (SM-G965F) with /e/OS (latest stable build).
My SIM card is PremiumSIM (Drillisch / o2 Germany).

Problem:

  • The modem can see LTE cells from o2 (manual network search shows “o2-de”),
  • but registration fails (“not allowed”).
  • In the service menu (##4636##), VoLTE is greyed out,
  • dumpsys ims → “Can’t find service: ims”,
  • getprop shows persist.dbg.volte_avail_ovr=1 but no IMS properties.

With “GSM only” the phone registers immediately and I can make calls and receive SMS.
With “WCDMA only” there is no network (3G has been switched off by o2).
So currently the only usable mode is GSM.

The same device with Samsung stock ROM works perfectly with this SIM in LTE/VoLTE.
This shows that hardware and SIM are fine, the issue is the missing IMS service in the /e/OS build.

Question/Request:

  • Is it planned to enable IMS/VoLTE in the official /e/OS builds for the S9+?
  • Is there perhaps a testing/dev build where IMS is already enabled, so I can try it?

Many thanks,
Mario

Regain your privacy! Adopt /e/OS the deGoogled mobile OS and online servicesphone

2

Did you already research the subject on the forum? Samsung have always used proprietary software for this purpose it has proved very difficult to reverse engineer but there have been (just) working demonstrations.

Realistically I think the answer is no for S9+ official.

I am not certain but the best chance of testing might be if you can search and find a GSI where this is being worked upon.

3

Search for “samsung volte” in these forums.