I'm posting this issue about the Yamaha RX-V992 receiver, but the more popular "big brother" model RX-V995 shares many of the same components and design so solutions for the V995 may apply to the V992.
My RX-V992 won't stay on. I had it in storage in the original box/packing materials in a temperature/humidity controlled environment for a little over 2 years. The unit worked fine just before I packed it up. I unboxed it just the other day and tried it--it powers on for less than a second then cuts out. It seems like some kind of auto-protection is kicking in. The unit has nothing attached--no speakers, no other components.
I have heard of power supplies and relays going bad, but during usage not during storage. I personally packed the unit away, so I know it was not dropped or banged around. I'm hoping this might be a simple issue that I could fix. Otherwise... well, these units sell for less than $150 in good used working condition in classifies/auctions, so bringing it to a repair shop is likely a waste of money.
Any constructive advice greatly appreciated! Thanks.