Change settings in build.prop


I’m not happy with the step size of the volume control of my Gigaset
GS290 when connected to a JBL Flip Essential 2 Bluetooth speaker.

Researching the topic lead me to 1, which suggests modifying
/system/default.prop, adding the lines


I’ve tried the following:

Installed adb on my Linux computer. Enabled ‘Developer options’,
‘USB debugging’ and ‘Rooted debugging’ in my phone’s settings.

$ adb devices
List of devices attached
GS290CTM904535  device

$ adb root
restarting adbd as root

$ adb pull /system/build.prop
/system/build.prop: 1 file pulled, 0 skipped. 1.6 MB/s (5177 bytes in 0.003s)

Up to here, this is successful. However, I cannot upload the modified
file to my phone again:

$ adb push build.prop /system/
adb: error: failed to copy 'build.prop' to '/system/build.prop': remote couldn't create file: Read-only file system

Also, I cannot remount /system:

$ adb remount
failed to remount partition dev:/dev/block/platform/bootdevice/by-name/system mnt:/: Permission denied
failed to remount partition dev:/dev/block/platform/bootdevice/by-name/vendor mnt:/vendor: Permission denied
remount failed

$ adb shell
GS290:/ # mount -o rw,remount /system
mount: '/system' not in /proc/mounts

How to proceed from here?


Regain your privacy! Adopt /e/ the unGoogled mobile OS and online servicesphone

I think this tuto covers all you need.

Xiaomi, faut-il rebloquer le bootloader - #3 by saroumane38. (English version below)

That did not work. As far as I can tell, the main change is modifying
the file’s mode, which fails on a file system mounted read-only.

# chmod 644 /system/build.prop
chmod: chmod '/system/build.prop' to 0644: Read-only file system

And remounting fails, as outlined above.

Hmmm … your “source” is mounting /system with TWRP …

You had Rooted debugging activated ?

Yes, I did:

However, I have not “rooted” my phone (and I actually do not understand the difference between the two).

Sorry, I do not understatn that statement: What is my “source”?

I was referring to this …

So, where should I go from here?

What If you simply use the “advanced, file manager” feature in TWRP to

  1. copy the files to an accessible place,
  2. Modify the file using an editor from your PC,
  3. Replace the file to its orignal place.