[Galaxy S6 Q&A, Help & Troubleshooting] orgler:
Hi,

I've got a German T-Mobile (DTM) Galaxy s6. Since I wanted to get the Nougat experience I used Odin to flash the VDF-Firmware. I did a full wipe. That gave ma an active CSC Code of "SIM". With that VoLTE and WIfi Calling are not working. As far as I understand this is controlled by other.xml/feature.xml.

So I tried to find a firmware/csc that has those features enabled. I've started with my current firmware by doing:

cd /system/csc

find . -name others.xml -exec grep -iH volte {} \;

This gave me:

./ATL/system/csc/others.xml: <CscFeature_RIL_SupportVolte>TRUE</CscFeature_RIL_SupportVolte>
./ATL/system/csc/others.xml: <CscFeature_RIL_BlockUssdDuringVolteCall>true</CscFeature_RIL_BlockUssdDuringVolteCall>
./ATL/system/csc/others.xml: <CscFeature_IMS_EnableVoLTE>TRUE</CscFeature_IMS_EnableVoLTE>
./MOB/system/csc/others.xml: <CscFeature_IMS_EnableVoLTE>true</CscFeature_IMS_EnableVoLTE>
./MOB/system/csc/others.xml: <CscFeature_RIL_SupportVolte>TRUE</CscFeature_RIL_SupportVolte>
./MOB/system/csc/others.xml: <CscFeature_RIL_BlockUssdDuringVolteCall>true</CscFeature_RIL_BlockUssdDuringVolteCall>
./MOB/system/csc/others.xml: <CscFeature_VoiceCall_ConfigOpStyleForMobileNetSetting>voltesettingscommon,voltesettingEUR</CscFeature_VoiceCall_ConfigOpStyleForMobileNetSetting>
./OMN/system/csc/others.xml: <CscFeature_RIL_SupportVolte>TRUE</CscFeature_RIL_SupportVolte>
./OMN/system/csc/others.xml: <CscFeature_RIL_BlockUssdDuringVolteCall>true</CscFeature_RIL_BlockUssdDuringVolteCall>
./OMN/system/csc/others.xml: <CscFeature_RIL_ConfigVolteRedialPolicy>OMN</CscFeature_RIL_ConfigVolteRedialPolicy>
./OMN/system/csc/others.xml: <CscFeature_IMS_EnableVoLTE>TRUE</CscFeature_IMS_EnableVoLTE>
./SWC/system/csc/others.xml: <CscFeature_VoiceCall_ConfigOpStyleForMobileNetSetting>voltesettingscommon,voltesettingEUR</CscFeature_VoiceCall_ConfigOpStyleForMobileNetSetting>
./SWC/system/csc/others.xml: <CscFeature_IMS_EnableVoLTE>true</CscFeature_IMS_EnableVoLTE>
./SWC/system/csc/others.xml: <CscFeature_RIL_SupportVolte>TRUE</CscFeature_RIL_SupportVolte>
./SWC/system/csc/others.xml: <CscFeature_RIL_BlockUssdDuringVolteCall>true</CscFeature_RIL_BlockUssdDuringVolteCall>
./TCL/system/csc/others.xml: <CscFeature_IMS_EnableVoLTE>TRUE</CscFeature_IMS_EnableVoLTE>
./TCL/system/csc/others.xml: <CscFeature_RIL_SupportVolte>TRUE</CscFeature_RIL_SupportVolte>
./TCL/system/csc/others.xml: <CscFeature_RIL_BlockUssdDuringVolteCall>true</CscFeature_RIL_BlockUssdDuringVolteCall>
./VD2/system/csc/others.xml: <CscFeature_IMS_EnableVoLTE>TRUE</CscFeature_IMS_EnableVoLTE>
./VD2/system/csc/others.xml: <CscFeature_RIL_SupportVolte>TRUE</CscFeature_RIL_SupportVolte>
./VD2/system/csc/others.xml: <CscFeature_RIL_BlockUssdDuringVolteCall>true</CscFeature_RIL_BlockUssdDuringVolteCall>
./VD2/system/csc/others.xml: <CscFeature_RIL_ConfigVolteRedialPolicy>VD2</CscFeature_RIL_ConfigVolteRedialPolicy>
./VDC/system/csc/others.xml: <CscFeature_IMS_EnableVoLTE>TRUE</CscFeature_IMS_EnableVoLTE>
./VDC/system/csc/others.xml: <CscFeature_RIL_SupportVolte>TRUE</CscFeature_RIL_SupportVolte>
./VDC/system/csc/others.xml: <CscFeature_RIL_BlockUssdDuringVolteCall>true</CscFeature_RIL_BlockUssdDuringVolteCall>
./VDF/system/csc/others.xml: <CscFeature_IMS_EnableVoLTE>TRUE</CscFeature_IMS_EnableVoLTE>
./VDF/system/csc/others.xml: <CscFeature_RIL_SupportVolte>TRUE</CscFeature_RIL_SupportVolte>
./VDF/system/csc/others.xml: <CscFeature_RIL_BlockUssdDuringVolteCall>TRUE</CscFeature_RIL_BlockUssdDuringVolteCall>
./VDF/system/csc/others.xml: <CscFeature_RIL_ConfigVolteRedialPolicy>VD2</CscFeature_RIL_ConfigVolteRedialPolicy>
./VDH/system/csc/others.xml: <CscFeature_IMS_EnableVoLTE>FALSE</CscFeature_IMS_EnableVoLTE>
./VDI/system/csc/others.xml: <CscFeature_IMS_EnableVoLTE>FALSE</CscFeature_IMS_EnableVoLTE>
./VGR/system/csc/others.xml: <CscFeature_IMS_EnableVoLTE>FALSE</CscFeature_IMS_EnableVoLTE>
./VOD/system/csc/others.xml: <CscFeature_RIL_SupportVolte>TRUE</CscFeature_RIL_SupportVolte>
./VOD/system/csc/others.xml: <CscFeature_RIL_BlockUssdDuringVolteCall>true</CscFeature_RIL_BlockUssdDuringVolteCall>
./VOD/system/csc/others.xml: <CscFeature_IMS_EnableVoLTE>TRUE</CscFeature_IMS_EnableVoLTE>

So obviously at least some CSCs in the multi-CSC-Firmware from Vodafone have those features enabled.

1) Would VoLTE (probably) work with a VOD CSC on german T-Mobile? It did with 6.0.1 DTM firmware

2) Can I switch from SIM to VOD or VDF? How do I do this? Without root? And if possible without another wipe?

3) If 2) is not possible: Is there another Firmware out there that brings VoLTE in the "default" CSC? Or how at all is that chosen?

Any glues would be highly appreciated,

BR

Johannes