This is a mod for XPOSED FRAMEWORK. If you don't have this mod installed, please read and download HERE.
This mod works simply by setting the config_safe_media_volume_enabled system parameter to false at boot time.
The mod is written by an XDA member called stammer and the app sources can be found on GitHub.
Installing and activating
- Download the mod HERE.
- Open the Xposed Framework app and install the binary if you did not before.
- Navigate to modules section and activate the mod.
Check out the original thread here for more info.