Music keeps stopping whle playing. How can I fix this problem?

To fix it, take all the music off it. Make sure its software and firmware are up-to-date after you do that. Then reload your music. That should fix it.

lol go to your music, play a song if one is not playing, navigate to the "now playing" screen if you not already there, in the top left hand corner you will see a oval type shape with a number 1 inside it, tap it, it should change to a grey or white color this means repeat is off, hit it again and the oval turn blue without the number 1 this is repeat all- to play in order turn off shuffle --Good Luck.

Press pause...

Maybe the hardware has been damage. find a local electronics repair shop near you and let them fix that for you.

try this, open your side bar on your screen, press the play options on your music player on your screen if its playing to stop the music, if it isn't, then press the music player for about a seconds till you notice it changes size and drag it to your side bar. by then the music player will be gone from your screen and back to its home in the side bar.. 
regards..

This might sound crazy but my dad had one and gave it to me and I took it apart to take a look inside and I think I have the answer. Some MP3 companies make the same mp3 a different type of chip. The main chil must have broke causing it to keep the screen lit but the music file or music archive in the chip got scrambled. The best way to get this fixed is to take it to your local electronics shop.

hope u got this fixed but if not i know where you can go to cobyusa.com and put the model number in product search the click firmware and download to ur desktop. open it up and u will have 24 grey boxes then plug in the mp3 and clik the firmware button right below box 24 one there is a green check in box 1 then its fixed and u can disconnect it and re add ur files

when you go to your music file and play a selected song. you will see two arrows in a circular formation and antoher set of arrows intersecting one another (shuffle). change the colour so both sets of arrows are grey by touching them.

why dont you use USB for that and fix it using your Nokia PC Suite. and after you copy and paste it to your folder you have to update it using your celphone.

You have to go on Sandisk.com and thay will let you
download music.