Dryer is getting too hot

Hi All,

We started noticing that our dryer is getting real hot to the touch. The other day we also smelled some rubber burning so I'm guessing the roller wheels ended up melting a bit. I checked the dryer and cleaned any lint in the exhaust line but didn't find anything (I cleaned it out around 6 months ago). I am guessing that the heater switch is somehow malfunctioning and is not shutting off. Is my assumption correct?

Thanks,
Nick