Left earbud's main driver not working

Whenever I get a new pair of these headphones, main driver in the left earbud stops working after a while. The wires tend to get jerked around quite a bit, often from getting caught on protruding doorknobs. I was wondering if this happens with anybody else, and if there is a way that I can fix it at home without damaging or cutting through the plastic pieces. It would also be nice to know if there is a way to strengthen or reinforce the wires somehow to prevent this from happening again.