To change your Keyboard touch sound,
Long press the VOICE SEARCH ICON on your keyboard.
There you will find ANDROID KEYBOARD SETTING, Open and go to ADVANCED SETTINGS and there at the bottom you will find KEYBOARD SOUND VOLUME SETTINGS and change the value to maximum (ie. 100)
For Touch and Lock screen sound
Go to SETTINGS > SOUND ( Explore this category, if found to increase the sound then Cheers :beer: )
If not then I suggest request to SLEAMBEAN ROM developer's they will increase the volume in their next update.
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