I am facing a strange problem with my S21 Ultra Unlocked which was directly bought from Samsung. I had enrolled into OneUI 4.0 beta when I was in the US. I was using Sprint connection then. I could see that, 'Service provider software version' is mentioned as SAOMC_SM-G998U1_OYM_XAA_12_0025 XAA/XAA, VZW/XAA.
I had to travel back to my home country (India) and I am using an Airtel sim card (LTE) here. Now, the strange problem is that LTE works here fine. But, VoLTE is not working. The network changes to 2G for phone calls. I am assuming that the autoswitching bands which was introduced in OneUI 4.0 is causing the problem here. I think since my software version shows as VZW, it's not registering the GSM bands.
Can anyone please help me here? The 2G network in my area is really bad and the calls get dropped quite often. I read some posts that we had an option to change local CSC in the older software, but it's not allowed anymore in OneUI 4.0.
I guess reverting to OneUI 3.1 will help, but that means a hard reset and again, I am not sure what is going to happen after the OneUI 4.0 stable release is out.
It is very disappointing to say the least and they know that this cannot be solved by the users and they are the only ones that can provide the solution.
Right now I have a Samsung Galaxy S21+ paperweight on my table and it cost me 900 USD, the most expensive paperweight I ever had on my table I would say.
Very Very frustrated and disappointed owner of Samsung Galaxy S21+
At least happy to hear that I am not alone with this issue. I had been thinking that there is an issue with my Airtel sim card. I was following up with the carrier for long.
Now, my test proves that it is indeed an issue with One UI 4. As you rightly said, my S21 Ultra is also a paperweight now.
I had posted this issue in the beta error reporting, they have replied back.
Interestingly they are claiming VoLTE is turned on internally but you proved it is not the case and I also see that when I see the phone information.
Looks like Samsung isn't going to help with this issue.
Ok... if they are not allowing to change CSC in Android 12 One UI 4, then what if we revert back to Android 11 UI 3.1 and change the CSC and install Android 12 One UI 4.
What do you think about this?
I don't think it's going to fix the issue. I think Samsung has to do something at their end to fix this.
What's your story? Which carrier were you on when you installed OneUI 4 beta? And which carrier are you on currently?
Installed One UI 4 beta with Red Pocket in the US to India JIO 4G. Also for your information, when I insert the red pocket sim and use the Samsung Band selector app, I can see the Volte option even now, but the minute I insert the JIO sim, it disappears and VOLTE option is frozen and cannot change. So it lead me to the CSC issue.
The above pic is S21 with Red Pocket sim
The same S21 with JIO sim, missing the VOLTE setting.
So conclusion, Samsung deliberately programmed to prevent the functioning of other country sims in US version.
My other grief is that, with UI 3.1 it is a Single sim phone, but with UI 4 it is a dual sim and I need dual sim phone for sure for work reasons.