I WAS FACING THE SAME PROBLEM FOR ONE WEEK. I HAD THIS ANDROID ASSISTANT INSTALLED. I WENT IN IT TO CLEAN UP CACHE.
THEN I SAW THE OPTION TOOLS IN IT. THESE IS ONE MENU BY THE NAME OF SOUND.
IN SOUND YOU WILL FIND SYSTEM SOUND WHICH WAS 0% IN MY CELL. AFTER MAKING IT TO 100% ALL SOUNDS WERE BACK .
SO JUST GO AND INSTALL THIS ANDROID ASSISTANT LINK IS AS FOLLOWS
https://market.android.com/details?...wxLDEsImNvbS5hZHZhbmNlZHByb2Nlc3NtYW5hZ2VyIl0.
AFTER INSTALL OPEN ANDROID ASSISTANT --> TOOLS --> SOUNDS --> SYSTEM SOUND --> SLIDE THE SLIDER TO 100%.
THEN I SAW THE OPTION TOOLS IN IT. THESE IS ONE MENU BY THE NAME OF SOUND.
IN SOUND YOU WILL FIND SYSTEM SOUND WHICH WAS 0% IN MY CELL. AFTER MAKING IT TO 100% ALL SOUNDS WERE BACK .
SO JUST GO AND INSTALL THIS ANDROID ASSISTANT LINK IS AS FOLLOWS
https://market.android.com/details?...wxLDEsImNvbS5hZHZhbmNlZHByb2Nlc3NtYW5hZ2VyIl0.
AFTER INSTALL OPEN ANDROID ASSISTANT --> TOOLS --> SOUNDS --> SYSTEM SOUND --> SLIDE THE SLIDER TO 100%.