maybe the orifice is bad? they're easily accessible. you'll see 2-3 screws on the top of the burner which come out and you can access it. you need a nut driver or socket to get them out. BE CAREFUL! you need to put tape or something sticky on your socket since they will just drop down once they're loose and you'll need to take apart the whole stove to get to them......ask me how i know!
Perhaps they put a set of Bubb Rub Whistle Tips on your stove.