Audio Systems: Speakers Problem, loud whistle, legacy series

Question
I have a problem with my speakers, when I turn the music on, the subwoofers are doing alright, but the speakers dont do anything, and I hear a sound like a pretty loud "whistle" for about 3 seconds (dunno where it comes from). Also I have two amplifiers (one for the subwoofers and another one for the speakers).

My speakers are:

2 5" Hifonics Warrior HCX52
http://www.sonicelectronix.com/item_3023.html

2 6 X 9" Hifonics Warrior HCX693
http://www.sonicelectronix.com/item_3025.html

And the amplifier for the speakers is:

American Legacy "Series 2" 600W LA490
http://www.sjgreatdeals.com/la490.html

Please help me, I really appreciate, Thanks.

Answer
sounds like you are about to blow the amp driving speakers. i guess you could temporarily hook up another amp in it's place to verify wether or not it is the amp that's bad. do more eliminating and get back to me, but i'm pretty sure your amp is the problem.....g....