I've got an old Sony Xperia Z running Cyanogenmod which is pretty unstable.
I'd like to remove Cyanogenmod & do a factory reset to the default Sony Xperia Z ROM. It doesn't need to do much - just run Spotify & Google Maps in our car.
However flashing a Sony Phone with a factory ROM requires a special tool (FlashTool) & a special file format (FTF).
Running FlashTool on Ubuntu 16.04 my phone connects in flash mode, but then reboots into Cyanogenmod after the "Preparing the files for flashing" step. I had assumed this was something to do with Cyanogenmod.
INFO - Device connected in flash mode
INFO - Selected Bundle for Sony Xperia Z(C6603). FW release : 10.5.A.0.230. Customization : C6603_1270-4066
INFO - Preparing files for flashing
INFO - Device disconnected
How do remove Cyanogenmod from a Sony Xperia Z & restore it to it's factory ROM?
If that isn't possible what can I replace Cyanogenmod with?