C500 MP3 playback problem

[Guest spwoodman]

When playing MP3s on our C500, sometimes for no reason and with no warning the music stops. The phone appears to still be playing - we can move between tracks and pause etc. But still no sound at all comes out. The problem isn't the headphones , as when they are unplugged, there is still no sound coming from the internal speaker. Restarting Media Player has no effect, neither does clearing evverything from the task manager. The only way to get things back to normal, is to turn the phone off and back on again, after which all is well until the next time. Any suggestions? Anyone else have this?