Trying to get surround sound speakers to work with...

Question

We have a 37 inch LCD37-207 Television and we have bought HCHKAW08 5.1CH Surround sound system, both Technika brand. We can get the Sub-woofer to work but not the other 5 speakers, we just get a hissing sound out of them. Is this a problem with the speakers or is it that the 2 are not compatible.Thank youGlenys