When ever I turn on my Bose speakers theres a high pitched static noise coming from them. I've had my speakers for about a year and a half and nothing like this has ever happened. One speaker is really bad, but the other speaker's static is a lot quieter. When i switch the speakers on the back of the woofer its the top plug that makes the unbearable noise. It was working fine an hour before, and I don't know what to do about it. Please help

SOURCE: bose companion speaker stopped working!?

What happened to you is probably mere coincidence with your cousin's use of the headphones and this is throwing you off. I own the Bose Companions also and they stopped working as well. However, I traced the problem to the "wall wart" power supply. Not sure why but Bose is now using an interchangable plug on them. If you look at the power supply you will see a "PUSH" button. If you depress it the plug can slide out. When it is slid back in and locked in place the connection between the plug plate and the power supply is not a good one. Try fiddling with it. But even if the connection is not the culprit, something in the power supply is. I swapped another power supply with the same connector and spec's ( amps must be the same ) from another item and the speakers worked perfectly.

SOURCE: Bose Companion II Computer Speaker: The AC power adapter burnt

My puppy chewed through the cord for my a/c adapter, I just took the speakers into Circuit City, and they found me a workable replacement (the replacement isn't BOSE, but it works just fine).  Hope that helps!

SOURCE: Bose desktop speakers stopped working suddenly

Make sure that the power is plugged into both the wall or strip and the back of the speaker.

SOURCE: Bose Companion 3 Series II not working (Mac)

The speakers seem to be muted by default - you'll see that the LED is yellow/amber. Tap the control pod - the LED will turn green and speakers will work. I felt like such an idiot after I spent almost an hour trying to figure this out. (This feature should be more prominent in the manual.)

SOURCE: buzzing static sound in speaker

Static can be caused by a few things.

Does the static persist if you unplug the audio cable from your computer?
If so, the static is being caused by the amplifier built in to your speakers.
If not, the static is probably caused by interference on your sound card. Try plugging the speakers in to a portable media player. You might need to replace the sound card in your computer.