When I try to add music to the game, this warning came out. What should I do to the code?

        self.daymusic = base.loadMusic('music/day.mp3')
        self.daymusic.setVolume(.5)   #Volume is a percentage from 0 to 1

My guess would be that your .mp3 file is corrupted. Try opening it and re-saving it in an audio editing program.

Keep in mind that using .mp3 files in a commercial game requires high licensing fees. I would recommend the use of .ogg instead, especially as we have a dedicated loader for Ogg Vorbis files in the upcoming Panda release.

Yes, that’s the problem. When I use .ogg file, the warning didn’t come out.
Thank you very much.