I just bought a pizza stone and everytime I try to heat it up at 500 degrees, smoke starts coming from underneath it, setting off my smoke detector. The first time I used it, I made the mistake of slathering it with olive oil..I know, I know, olive oil doesn't do well at high heat, I just wasn't thinking at the time. But I rubbed the olive oil off but it won't stop smoking. This is my second time trying to use it. Has anybody else had any problems with a smoking pizza stone?