Usually when one of those CV joints break, that boot is all torn and the grease gets all spun out. When the joint drys up from lack of grease is when they break. I've also seen where ball bearings and pieces of the bearing cage will fly out on the ground when you put the car in gear. It will make quite a noise as well. It's really hard to say what is exactly wrong with yours without seeing it. Also hard to determine what it would cost to repair. So you don't see any damage on those boots and any parts falling out? When you put it in gear where do you hear the noise coming from? If I had to guess it would be the passenger side CV, that's the side I see broken all the time.