How to troubleshoot power failure of stereo?

Hello! I'd like to troubleshoot some apparent power issues with my Panasonic SC-HC57 stereo. When turned on, it will play music for a few minutes and then mysteriously shut off. It then won't turn back on (power light flickers red and then off) unless it's unplugged and left for about a day.

I am a novice with electronics repair, but am very eager to learn, and have some solid experience repairing desktop and laptop computers. With the need to leave the stereo unplugged, this makes me think it has something to do with a power supply, fuse, or a capacitor, but these are all novice guesses.

Any initial tips (e.g. necessary tools, introduction to basics, guides, etc.) on how to troubleshoot power issues with a stereo would be greatly appreciated. Thank you all so much!