Buzz from front speakers...

Have you sawpped the speakers out to make sure that it's not a blown tweeter?Are these modles new or older (surrounds can cause noise if they have deteriorated).Forget about the wires as you'd notice if it were rusted or had major kink/short.Most like;y it's in the reciever but swap the speakers to make sure there nbot blown.Overdriving or playing to loud causes distortion and the distortion will create heat and ultimately blow them.But you usually damage speakers by UNDEREPOWERNG i.e. trying to get more volume then they are capable of or in more cases your amp is not powerfull enough for insensitive speakers,their is clipping (on an aoscillioscope the rounded wave form looks sqaured off not round therefor is "clipped")and ultimately the power isn't there cleanly heat and blown speakers result.But I think it is much more likelly that the amp needs repair and it is not set up.But switch speakers to see if they are demaged first to see if good ones work where bad ones are.If the speakers aren't damged bring amp in for repair.
Chazz

No problems with your set up. Are the noisy speakers wires near other electrical cords? Otherwise, I would guess the reciever.

Is the buzz present when no music is playing? I'm assuming you've put your ear close to the speaker drivers to make sure that is where the noise is coming from. It'd probably help to identify if it is a high frequency buzz from the tweeter or a lower buzz or hum from the woofer. If so, then the amp, preamp or source electronics are likely picking up interference somewhere. Could be anything from a light dimmer on the same circuit, an RFI source or similar. First see if the buzz disappears/reappears when various electronic and electrical items in the home are switched off and on.

If the buzz only accompanies music and gets worse with bass heavy passages, then something in or near the speakers is rattling when it shouldn't. It is likely not the speakers themselves since it is not common for two speakers to go bad in the same fashion at once. Again, find something that generates the buzz and start nosing around.

The buzz is occuring when the volume control is turned up too much (usually above 47) or so. It happens whether the music is playing or not. The Rear Speakers don't seem to have the same issue, and it happens no matter how close the fronts are to the unit, and even when all EMI is close to eliminated.

-j.