I found many Android ICS Users with problem with the Music Player, It continuously gives an error that "Sorry, file format not supported"
First Of All Please Simply Restart Your Phone And See If It Works Perfectly
There are few ways to fix it :-
i) This Method Worked For Me:
=> Go To Menu > Settings > Apps.
=> Tap On "ALL" On The Top
=> Search For "Media Storage" and tap on it and Then Tap On "Force Stop" && "Clear Data"
Do The Preceding Procedure For "Music", "Music FX", 'And Every Music Player App'.
=>Then Close Settings And Open Your Music Player App
You Will Find That All Your Song List Is Not There,, DoN't PaNiC (But if they are there then follow the above step once again[just once])
=> Now Restart Your Phone OR Tablet OR any thing you are working on.
=>You are almost done: now open the "Music" app
=>Wait 5 Mins. so that it loads it loads all your songs
=> Then Play One Of Your Songs And See If It Works
ii)If The Above Didn't Worked for you :-
=>Simply Shut Down Your Phone OR Tab.
=>Remove The Storage Media (If You Use Internal Storage Then Remove Your Battery)
OR Turn On Your Phone And Press The Power Button Until The Screen Goes Black (Do It On Your Own Risk)
=>Then Turn On Your Phone And See If It Worked (Turn Off It And Insert Your SM And Turn It Back Again)
=>Open Your "Music" App And Open Your Song
iii)Now If Even The Preceding Two Didn't Worked For You :-
=>Then, Open Your Settings
=>And Do A Factory Reset("WARNING" You Will loose All Your Data)
=>And It Will Work
This Is Caused By The Simple Misbehavior of the app, And If all of the above Didn't Worked For You, Then Contact Me Or Contact Your
Sorry For Any Mistake, & Feel Free To Ask For Any Help