I'm working on my parent's computer with an Antec Earthwatts 380 that makes a high pitched whine when the computer starts up. It doesn't whine right away, usually starts 10-15 seconds after Windows is loaded, and only lasts for 30 seconds or so. The whine increases in pitch until it goes away. After it goes away, it doesn't come back as long as the system remains on. I'm not too worried about it, but my parents are annoyed by the sound and it makes them feel like the unit is going to die.
It has done this since the very beginning, so it's not something that has just developed over time. When the unit was new, I had to rotate the power plug 180 degrees to mount it inside their Cooler Master Elite 360. The power plug was the only thing I touched inside, and I made sure that none of the wires were touching before zipping the PSU back up. Any ideas about how to fix this? I've heard of hot glue, but I'm not sure where I would need to apply it or what type to use.