I was having some issues with old mp3s being indexed in the Database. openMobile kept trying to play mp3s that didn't exist anymore.
So, I wrote a quick plugin to clear the index, and have an option to start indexing again after clearing.
Simple plugin, but I thought others might have a use for it. This is only necessary for Versions < 0.9, because it looks as if this exists in the 0.9 code by default. The code actually exists in 0.8 as well, which my plugin calls. There's just no way to access it through the GUI (that I found, anyway).
You just assign ClearMusicIndex to a button. When you click on the button, a screen pops up with a checkmark for starting the index after clearing, and a button to clear. There will be a status message if it's successful or not.