I'm not sure if this is the correct place to post a question like this, but here we go.
I recently purchased some LED strips for some backlight on my TV. Admittedly, these backlights are of the "cheap Amazon purchase" variety (although not the absolute cheapest out there). The LED lights are powered by USB, which I have plugged in to the back of the television.
I also had some old-ish Klipsch speakers (two satellites and a subwoofer) that I decided to try to hook up to the TV as well. The speakers connect to the TV through an 3.5 mm AUX cord. However when the speakers are powered on and connected to the TV, I noticed that there is a high pitched buzzing coming from both satellite speakers. I can make the buzzing stop if I disconnect the LED lights from their USB power. Also, If I connect the LED strips to some USB power source other than the TV, I can have the lights on with no speaker interference. The problem with that however is that then the LED lights are always on - as opposed to when they are powered by the TV USB outlet, in which case the lights only turn on when the TV is powered on. Obviously the latter is much preferable.
And I'm not sure if this is relevant, but the TV and speakers are currently powered by different wall outlets.