Yup I spent about an hour to figure out how to get it working, the foolproof way is to put the .ogg file in your custom, but when you get new versions, you gotta do it again.
The official way, is to convert your music file to .ogg using
this. It's what I used. Before uploading your music make sure you got .ogg selected, and set it to the highest quality (extreme). Try to make sure your song isn't longer then 2 minutes, as the bigger it is, the longer it takes to upload. Then upoad, download it. Once you're done that, go to the music item choose the .ogg file wait for it to upload, and that stuff( might take a couple minutes). When it's done name it do whatever but most importantly make sure it's done correctly. If it is when you click the edit button, you should be able to play it in you're browser. If you can do this then you know that you did it properly. Hope that this helped some people.
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Edit: Also make sure that you have version 4.2, as this is what I used, as far as I know from what Hampa said, it's not possible to listen to music right now on a version lower then 4.2, since that's when he added the music option (spoken like a bug tester)
Last edited by Dscigs; Nov 5, 2012 at 10:57 PM.
Reason: <24 hour edit/bump