First I installed the Clock Work Mod (CWM), it was easy I just follow this page:
$ adb reboot bootloader $ sudo -s # fastboot flash boot S_DooMLoRD_AdvStkKernel_FW-96_v3.elf sending 'boot' (9244 KB)... (bootloader) USB download speed was 36833kB/s OKAY [ 0.272s] writing 'boot'... (bootloader) Flash of partition 'boot' requested (bootloader) S1 partID 0x00000003, block 0x00002000-0x0000bfff (bootloader) Erase operation complete, 0 bad blocks encountered (bootloader) Flashing... (bootloader) Flash operation complete OKAY [ 1.831s] finished. total time: 2.104s
Then I restarted the phone keep pressing VOLUME_UP to enter on CWM recovery mode.
In CWM menu I cleared data/cache (factory reset) and installed these files:
Update: I use rVoix calling recorder program and this is the configuration that worked for my Xperia S:
Android version: 4.1.2
Kernel version: 3.0.58-FXP+ (Sat Jan 19 23:15:35 EET 2013)
CyanogenMod version: 10-20130119-UNOFFICIAL-nozomi
cm_nozomi-userdebug 4.1.2 JZO54K eng.
This is rVoix version I’m using: rvoix_mod_kaefert_v2.apk !
A strange thing I noticed: rVoix doesn’t work the first time I run it, after restarting the Android the rvoix service starts but the icon doesn’t appear in the notification area and the audio format selected (MP3/AMR) is ignored and it always save only WAV files.