I can hear a major buzz coming from a power strip that I have even with no load on it. What could be wrong with it and should I bother fixing it or just toss it out and buy a new one? And also is there any hazard to use that power strip?
It likely has a small SMPS inside to run the LED and any additional gadget. Something seems to be failing if it is loud. If it is just barely audible, it could just be a resonance with the mounting frame that is vibrating. The magnetic field can cause the metal around the SMPS to vibrate in the audible range.