Mi A1 not able to make calls into German landline network

[hein-erich]

Hi there,

I have a Mi A1 with LineageOS 17.1 that works fine, except that I cannot make phone calls to German landline numbers. I just hear some very distorted noise from my opposite, while he doesn't hear anything from me at all. Calls into the mobile network work fine.
The problem has already occurred before upgrading from 16 to 17.1.
The problem occurs for both SIM slots. After ejecting the SIM card and inserting it again, sometimes one or two calls are possible, then the error occurs again.
I have another Mi A1 (with a broken screen, though), which works fine.

Does anybody have an idea, if it is a hard- or software problem? Any ideas how to fix this problem? I would be thankful for suggestions.

Cheers
Hein-Erich

 

[saski4711]

Hi there,

I have a Mi A1 with LineageOS 17.1 that works fine, except that I cannot make phone calls to German landline numbers. I just hear some very distorted noise from my opposite, while he doesn't hear anything from me at all. Calls into the mobile network work fine.
The problem has already occurred before upgrading from 16 to 17.1.
The problem occurs for both SIM slots. After ejecting the SIM card and inserting it again, sometimes one or two calls are possible, then the error occurs again.
I have another Mi A1 (with a broken screen, though), which works fine.

Does anybody have an idea, if it is a hard- or software problem? Any ideas how to fix this problem? I would be thankful for suggestions.

Cheers
Hein-Erich

I have the same issues with stock ROM since June when making VoLTE Calls into any network (mobile or landline) in Germany. Try to disable VoLTE (4G Calling) in your SIM settings. At least that helped on my device - however falling back into GSM is a terrible workaround!

 

[hein-erich]

I have the same issues with stock ROM since June when making VoLTE Calls into any network (mobile or landline) in Germany. Try to disable VoLTE (4G Calling) in your SIM settings. At least that helped on my device - however falling back into GSM is a terrible workaround!

Thank you! This actually helps and makes my phone usable again!

It is still puzzling why this phenomenon occurs for one device and not for the other, why it occurs only for landline calls in my case and for all calls in your case, and what has made this phenomenon to occur at all. But at least: there is a workaround! Thanks!