If use some apps which create mediafiles which appear after some time in
the mp3 player.... and just hitting play all stopped to make fun because
it also plays non-music-mp3s...
Solution - Exclude Directories from Media Scanner:
Create in every Directory which you want to exclude a file with the name
.nomedia . You can use something like es explorer to do that. or you can
use http://market.android.com/details?id=ch.droida.nomedia
after that you have to restart your phone to get your change recognized
by your system (media scan should run on startup)
in my case i had to clear the data of the application media storage:
Go to settings.
Click All Applications tab.
Click Media Storage.
Click Clear Data.
Click OK.