I recently bought a set of MKIVs from a friend, and the minute I got them home I loved the way they sounded, but when I turned the volume up above 73 db the mid range driver in the left speaker seemed to cut out, then I started hearing some noises that sounded like the driver rubbing during the low frequencies and wouldn't play the frequencies it was supposed to play, so I immediately muted the volume. I decided to rest the system and come back, and the mid driver still made a rub, or farting type sound during the lower frequencies... so I removed the mid driver, examined it, and found that it was in impeccable shape, based off of my limited knowledge, but when I put the driver back in the cabinet, it worked! As I turned the volume up, excited to have these amazing speakers back, it happened again? Anyone have any clue as to what is going on, the driver works fine but clearly something is wrong.... please help! (also, the right speakers mid driver stays fine as the volume goes up, and there is no distortion from the right speaker, so from what I understand, I'm not pushing the driver past it's excursion by playing it too loud)
