Can you make a super small waterproof prototype mp3 player?

I am looking for someone to build a prototype mp3 player that would have the following specifications. 

- circular housing and no larger than a U.S. nickel in diameter.
- top of the housing would have an insertion for a 1/8 headphone jack.
- the height could about 1/4 inch to a 1/2 if need be.  (the smaller the better)
- the housing must be waterproof.
- the player will autoplay one song when headphone is inserted.

Please feel free to contact me here: jacobaa7@gmail.com

Thanks,
Jimmy

trialex5 years ago
OK I thought more about it

- Does it HAVE to be mp3, or did you use that term as a generic music player? Can the music file be converted to a .wav file?

- Does the song need to be able to be changed, or can it be permanently set to a single song on assembly.
trialex5 years ago
The size requirements are tough - what power source are you planning on using? Even a single CR2032 would take up a significant proportion of the envelope, never mind the PCB/components (of which the jack would be the biggest)

Also there must be a source of waterproof headphone jacks out there, but I haven't seen them in any of the usual hobby suppliers.

Might be easier to achieve both the size and waterproof requirements if you allow the headphones to be soldered directly to the board.

Is there any reason why the slightly larger commercially available waterproof mp3 players designed for swimming wouldn't work for you application?