I've had my set of 2PI's for about four years now. The eminence driver in the right speaker malfunctions intermittently. Sometimes sound comes out of the tweeter but not from the woofer, and tapping the woofer cone makes it start making sound and generally continue. Increasing the volume can also make it start playing sound.Does this mean there is some sort of loose connection inside the woofer? Is it reparable? How do I get a replacement?