In my ford explorer every time I drive I can barely hear my music and I hear mostly my engine

Bad muffler or other exhaust system problem?

Have you had a windshield replaced recently? Also, look down behind the brake pedal where the steering shaft goes through the floorboard. Can you see light through the rubber dust boot?
Both of these areas can cause excessive engine noise into the cabin and not insulate the sound.
Other than that, I'd be looking into what Tx ^ was asking you.

Turn your radio up! :)