One of the woofers on my right speaker crackles when it hits a certain frequency. At other frequencies it doesn't do this, so at first I thought it was just a random occurrence. I've isolated the sound to the speaker, so it's definitely not coming from anything else. Why does it do this, and is there anything I can do to get it repaired?
Make sure the woofer is securley attached to the cabinet. Also, take out the woofer and make sure the wires are secure on the driver itself. If that doesn't work, switch your left and right speakers and see if it makes the crackling sound on the different speaker. Also check out the crossover and make sure everything looks fine. My guess is a loose connection or the crossover got damaged. If all else fails, you may have blown it. If it's blown the only thing you can do is ask klipsch if you can buy a new one.
I had a pair of Legend 10's and had the same problem. Opened them up and was appalled at the wiring and connections. The culprit was a loose connection. I went my usual overkill route and soldered monster wire between all speakers. Problem cured.