Audio Systems: Outdoor Stereo, bluetooth audio transmitter, marine speakers

Question
I play on a field sport.  We are looking for a speaker to play during practices, games, etc.  In the past, we have used the "ION Block Rocker Battery Powered Speaker System for iPod" but have had problems with it.  The battery stopped working and the handle snapped within about a week of getting it and the ipod connection has always been finicky.  Do you have any other suggestions of a loud stereo to be used outside?  I also live in Oregon where it rains quite a bit so something with a bit of weatherproofing would be ideal. Any suggestions?

Answer
I am a car audio expert, not other home or portable equipment. but you did ask the correct person my kid is a cheerleader captain and i have to go with her all the time so i been on the same boat with the music and portable speakers, in a big football area in my case after couple of broken units i was able to park near the lot and i purchase two marine speakers,
with 20 feet of wire for each and use my car stereo been working great for the past year

I also add a bluetooth audio transmitter to my factory car stereo so i can use my phone from outside the vehicle to change the songs  they make this for iPods and android and it all depends  on the radio or your vehicle

I use BOSS AUDIO MARINE MR30 pay $60.00 for a pair  and i let them play in the rain still work

Android blueetooth adapter