Clipping Question

[weeboy]

I've been experiencing snapping noises from my NHT sb speakers at what I would not consider to be overly loud levels. The local audio store replicated the noise with his big ass amp and said the speakers were being over driven.
I came home and played with it a bit and found they do not clip in digital only in stereo
mode.
What I did find is there is a "loudness" button on the receiver to boost bass response when listening at lower volumes. With this switched off the clipping did not occur.
My question is -would this have been what the problem was and why did it occur?
The snapping noise was very pronounced and concerning when it occured.
I wouldn't think the fix could be this simple.

[This Guy]

If you have the loudness control on (boosting bass and treble frequencies) it begins to stress the speaker. In your case, the bass was too much for the woofer to handle, so it bottomed out. If you keep listening to it when it bottoms out the woofer will be ruined, take the loudness control off. This will be common if you don't have a subwoofer cause you are trying to keep the bass as loud as the midrange, but the woofer hits xmax earlier because it's running full range. Take the loudness off and try to invest in a sub.

-Joey