Never heard of electronics suddenly creating a speaker "chirping" sound phenomenon. ONKYO has a well-known and well-travelled lengthy legendary poor track record of HDMI board failures, but that is USUALLY a catastrophic failure in nature and easy diagnosis , and not a "chirping " in your speakers.
Q: Have you first considered and ruled out that your speakers are the culprits (sudden power surge fried them, caps gone, high listening volume and sudden amp headroom limits exceeded created a transient clipping that fried them , ???)
I would rule that out first before I journeyed down a slippery slope of receiver expensive diagnostic and repair services, the cost of which will likely greatly exceed the unit's FMV. In that case, probably not worth it to fix.
Q: Have you first considered and ruled out that your speakers are the culprits (sudden power surge fried them, caps gone, high listening volume and sudden amp headroom limits exceeded created a transient clipping that fried them , ???)
I would rule that out first before I journeyed down a slippery slope of receiver expensive diagnostic and repair services, the cost of which will likely greatly exceed the unit's FMV. In that case, probably not worth it to fix.