Distinct relay click every 10-15 minutes or so, what is my Onkyo reciever doing exactly?

[LloydLynx]

Every now and then my Onkyo TX-8220 makes this relay click sound, usually right when the bass hits, but it could happen any time. It sounds like it's coming from the power supply side, and doesn't seem to affect the audio quality in the slightest. This started happening after including an EQ and tuning it. My guess would be the PSU is switching between power levels, but that would mean the receiver should run hotter when that happens, which it doesn't. My curiosity has been growing the past few weeks, so I'm here asking if anyone knows what it's doing and why it's doing it?

[circeseye]

that sounds like a overload circuit. it may be overheating and or a component may be on its way out. once that starts it usually will just get worse