I want to understand in a more detail how android is working because I have a specific problem with the cellular network.
On my galaxy s4 i9505 I was running a CM11 Snapshot M9 for a while without a problem.
It's ok but I often wanted to update to the latest CM11 builds (Snapshot or Nightlys) but there seems to be a problem with my cellular network.
The thing is, my provider is "yesss!" which is a discount mobile provider in Austria. With the M9 build the correct network is found and automatically connected. On all newer variants there is no automatical connection.
When I search for cellular network providers I only find the bigger ones like "A1", "Drei", "T-Mobile", ...
I can connect manually to "A1" which is a roaming partner of "yesss!" but it won't reconnect automatically and it is detected as roaming (which is correct). So basically the modem is working but there is no cance to find a connection to "yesss!"
How does it work?
I found out that even on the newer builds, the same modem is used.
I tried: I9505_XXUDMGG_MODEM.tar and later I9505_XXUDMHI1_MODEM.tar
both work with CM11 Snapshot M9 but are not working with newer builds.
So it may seems to be no problem of the modem?!
I tried to go to the "*#*#4636#*#*" menu and checked the settings:
on both versions "LTE/GSM auto (PRL)" is configured, so also no difference.
I tried some inofficial CM12 builds and other Andorid 5.0 builds.
Allways the same... The roms are working fine but the can't connect to "yesss!". only "A1" is possible.
Does anybody know what I could do?
Please help. Right now it seems that I am stuck at an old CM11 build.