Altec Lansing Speaker Buzz (2 Speakers, 1 Subwoofer)

TechSpot Users,

Don't worry, I've already did a search in this forum with the key words "Speaker buzz", and nothing of significance showed up. So I'll try and explain my problem.

My speakers, when turned on, will produce this buzzing sound that goes like "Bzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz".

And yes, it does not fluctuate, not in a cyclic sense, it's just a single tone of "Bzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz".

Now, the odd thing about this is, if I unplug the Audio Jack to my Laptop, the speakers will still produce that sound, regardless if it is plugged in or not. My laptop is appxorimately a good 30 centimeters from each speaker, and the woofer is underneath the table. Also, no, my Laptop's WI-FI is turned off. If I do turn it on, I get the occassional random inteference, but that's not what's causing the problem. My network runs on cables too.

Now, to clarify more things, if I use headphones, and plug it in to the audio jack, the sounds are perfectly crisp and clear, with no signs of buzzings whatsoever. (This is how I rule out that it's not a sound card problem)

If you're wondering whether my speakers work, yes, they work perfectly fine. Everything works as it is, but if I don't turn it up loud enough, even in the background, I can hear that buzzing sound, which really annoys me. Here's an interesting fact to help, if I turn on my desk lamp, the buzzing gets significantly louder as well. Please note that the speakers and the lamp are on two completely different power sockets. (They could be connected in terms of wiring behind the wall )

So, any ideas or takers on what seems to be the problem? ( I bought these Altec Lansing Speakers in October, 2006, and when they were first used, they never had this buzzing problem ). Is this the result of old age or...?

Cheers, and my apologies for the amount of details. I just wanted to save everyone the time of having to ask all the minor questions.

i've had a similar issue with my altecs, from my (admittedly crude) tests, it seems to be an issue caused by poorly shielded wiring in the speakers. however i have heard a very slight buzzing when i use my pair of headphones that uses alot of power. i got my set around the same time as you so maybe there was a bad batch.
you said your laptop wi-fi is turned off, is your wi-fi router is still on? or do you happen to have a cell phone or a cordless phone within 10-15 feet? lastly are they plugged directly in to the wall socket? i found that when i switched to a good quality UPS the hum in my set went down significantly.

in my set the problem didnt start until after my system had been surged during a storm (no damage, not even to my surge protector, but it did cause a restart). so maybe its damage...
hope this helps a bit,