Another question about MP3 Soundwave

Question on the memory card. I picked up one from Staples (1 gig) and I moved a couple of .mp3 songs over just to see how it would work, but nothing played. Do I need to format the card first, or move the music over via Windows Media Player or iTunes? I also noticed that the Rumble & Frenzy headphones have an adjustment switch to control volume. Do I need to get amplified headphones as well?
Does anyone who have MP3 Soundwave able to get music to play?? What did you do to transfer the media over?
Any and all help is greatly appreciated.
Does anyone who have MP3 Soundwave able to get music to play?? What did you do to transfer the media over?

Any and all help is greatly appreciated.