Cant hear parts in music...(Logitech Z5500 5.1, Audigy ZS 2)

OK, i just got the Logitech Z5500 5.1 Surround sound speakers with a Audigy 2 ZS sound card and im running into a problem. When im listening to my music, when it gets to some parts in a song where a lyric should be or a drum part or guitar part, it just wont play it..or it plays it really really really really really low in volume so low you just basically cant hear it. All the other parts of the song plays it just fine, no problems. I play it over again and it doesnt play that same part again. And it differs between songs. Its really weird; whats going on!? I did a test and all the speakers are working, got all the right drivers, all the right programs..

Did you do a speaker test from the Creative control panel or the speaker's control pod? Check all of your connections on the back of the control pod as well as the back of the computer. If that's not it, go through all the settings in your creative control panel and double check all of the mixer and output settings to see if one is off set.