ive got a Dell DJ MP3 player. I decided to get one of those cassette adapter things so i could paly it through my car stereo, but the ones at wall mart and best buy cost like $20 so i bought one for $5 from a local softwear outlet place. I used it in my '81 rabbit but the stereo in it sux really bad so i eventually just got this rechargeable speaker to hook my mp3 up to. Someone told me that the output on the mp3 player is different from what some of the cheaper cassete adapters use and that it could screw up my stereo, is this true?