Thanks for the replies and information.
On my receiver, I have a setting in place that allows the max volume to be -10DB so it's not completely maxing everything out. I basically have this in place for those social days when people are over and someone(or me) gets a little over eager with wanting things real loud.
Yesterday the volume was cranked up on the system to -10db. On my center channel speaker, which is the Klipsch RP-640D, a "snapping" sound could be heard at certain points in the song when heavy bass would kick in. The speakers are set to small and I have a sub in place. The song is a rap song w/a lot of bass, Juicy J - For Everybody.
I've never heard this issue before although not a lot of rap is usually played on my system. And I have only had these speakers for about 4 months. After hearing this, I obviously turned down the volume but was quite surprised it could have happened given the volume limit I have in place, my receiver power, and quality speakers in place. With the volume a little lower, the issue does not occur. I'm currently going through my settings to see if there is something else possibly causing it as well.