Macbook Air will not read my Harmand/Kardon speakers

Hi,

okay, here we go. I am New to apple i do not know much about it. I am having trouble with my USB port reading my computer speakers(Harmand/Kordan sound sticks.) evrything else will work just fine when pluged in to the USB port, except for the speakers. I have pluged in the speakers to other computers to test and they do work, just not on my Macbook Air. hope someone can help. thanks