Search for a cure ... to boredom
A waterproof, functioning mp3 player is something of a holy grail for swimming. Actually, it's relatively easy to just waterproof something -- but making it into a working solution for music is much harder. The problem is delivering audio to your ears. See, we normally get sound through the compressions and rarefactions vibrating through the AIR, and there's not a lot of that underwater. So manufacturers try to build waterproof buds that won't short out if they get wet, but still have to seal up your ear such that there's a little air trapped inside, and then they deliver sound just like other headphones do.
The problem is that these things almost invariably fall out of your ear in the first lap or so. We've tried it with a number of different headphones, and that's always the case. It sucks. Finis went for a different approach with their phones - they're bone conduction phones, so rather than rely on the air, they just vibrate all on their own, and when you wear them, they resonate with your skull and deliver audio without needing any kind of seal.
So how do they work? Check out the video above. The quick answer is that yes, they'll deliver audio, and actually, it sounds pretty good! We had issues trying to maintain that audio quality once we started swimming - the sound of your own breath and water rushing by your head is enough to really drown out the sound, even at the Swimp3's highest volume setting. Tweaking the precise position of the Swimp3 on your head can improve the situation slightly, but so far, the Holy Grail is still a few steps away.