A few years ago, I got called to tune a piano. The lady of the house said it was making "strange noises". When I played it, the piano sounded like it was at the bottom of a swimming pool. Hmmm....

When I put the hammer to the tuning pins, they slipped around quickly instead of holding tight. 

I asked her, "Have you used any cleaning products around this piano lately?"

"A few weeks ago", she said, "I noticed mice droppings in the bottom of the piano". (By the way, mice LOVE pianos - the felt is yummy mouse food)

"I bought one of those bug bomb aerosol cans", she continued, "popped the top of the piano, placed it inside and turned it on. Then I closed the piano, hoping to kill the mice."

I was the bearer of bad news that day. Dead piano. Total saturation of oil into all the internal wood surfaces. 

I know you would never do this.