It is likley a small cooling fan with bad bearings. I don't know how widespread the practice is, but I know there are a few consoles with a fan for the
power supply. It's done in an effort to keep the
console compact, light weight, and inexpensive. If the fan is making noises, it is getting ready to fail. A dead fan will shorten the life of the
power supply.
Fans are relatively easy to replace. If you can locate the exact part that is best. If not, they are made in standard physical configurations and operating voltages that can be matched. The fan wires will have to be cut and spliced with solder and shrink tubing. I don't know if A & H parts are easy for an end user to obtain, but that would be the place to start.
My rant for manufacturers: In recent years, small fans have becoming the most common failure
point in electronic equipment. If a fan is put into a piece of equipment, it needs to be of decent quality! I have seen fans run for decades and I have seen them repeatedly fail in a few months. The latter is all too common. Audio equipment is assumed to be silent in operation. If it isn't, disclose that in the specifications. Nothing ticks me off more than to get a noise maker that I can't use in a quiet studio.
