If you're using a Revlon one step hair dryer and notice that it smells like it's burning, there are a few possible reasons. The most likely explanation is that the dryer is overheating. This can happen if the dryer isn't used properly, if it's old or damaged, or if it's been used too much without being cleaned. Another possibility is that something is caught in the dryer's vents, preventing proper airflow and causing the unit to overheat. If you think this might be the case, you should unplug the dryer and check for any debris that might be blocking the vents. Finally, it's possible that the smell is coming from something else entirely - like your hair products or an object near the dryer - so be sure to rule out other potential sources before assuming it's coming from the dryer itself.