Alan makes strong point here Jinhan.
I've played around with test tones rather extensively in the search for answers on a strange piece of music that was causing some reverberation in one of my M60 drivers. There really was no easy answer to be found. Sometimes particles hit a certain resonance putting molecules into a similar step beat causing detrimental things to happen.
Anyone ever read about the army crossing the bridge while walking in step and causing it to collapse?
There is sound physics behind this.
Ultimately if you cannot honeslty hear it with normal playback material, i would ignore the artifact. Otherwise you may drive yourself mad.
