Weird Exhaust Smell

The last two times I've ran my RTV I've noticed a strange burning smell. It's running perfectly fine. The first time I thought maybe salt off the roads on the exhaust. Even though I never smelled it last winter. Today I narrowed it down to the exhaust itself. IT SMELLS LIKE GRILLING MEAT! Do you think a mouse could've actually died inside my muffler? I've checked over the rest of the machine, no nests or debris anywhere.

Weird Exhaust Smell