By Nancy from Cumming, GA
I think you need to call the piano tuner and find out why this might be. Have you or anyone spilled anything on or around the piano? Or do you or anyone eat snacks when sitting at the piano? And do you possibly have a mouse problem or a kitty cat that might be getting on the piano? Best thing is to call a professional.
You didn't upset the piano tuner did you? lol
Piano tuner may have used something like fish oil when oiling moving parts - I know they use fish oil to prevent rust in cars - you should contact the tuner and ask/tell him - he may have a solution for you!