1998 Ford Explorer Burning Rubber Smell

The following two factors may be relative, but I'll let you be the judge. About a week and a 1/2 ago, I noticed that the parking brake light wasn't lighting each time it was engaged, although it seemed like it was properly disengaging. Last night was the 2nd time I've noticed the "burning rubber smell" after driving approximately 8 miles. At first, I smelled it while driving late at night, little to no traffic, no construction, and thought it must be road/asphalt smell. However, when I arrived home, and exited the vehicle, I smelled it rather strongly. I stopped and smelled, and it appeared to be coming from the middle of the vehicle, not from under the hood. I specifically went to the hood and smelled, but it was the normal smell. As I walked past the vehicle I smelled strong burning rubber again. Is this indicative of a brake problem? But for this, the truck has been flawless!