from the information you've given us the problem is,
'I put a cd in, and I dont hear a sound'
In order for anyone to help you hear a sound from said speakers, we need more info
Do you have a soundcard in your system?
Are the speakers plugged in correctly?
is the fuse in the speaker plug ok?
is it muted in volume panel?
There are so many possibles you need to narrow things down a bit for us,
Go into your control panel, look for speakers and sound properties, have a little look round in there for default devices, whether things are enabled or not for playback, make sure your sound drivers are up-to-date, check all this and come back if you still have problems, we can help, but we need you to help us to I'll look back in a bit mate ok