just a quick question, it may or may not be stupid

something that has been concerning me. When playing some presets I hear I a pop ( a sort of short tinny percussive sound) in the tweeter of the speaker. Happens mostly with the bass presets with very low attack on the volume, for example wreck*bass on the aniv. presets. The sound goes away when I move the attack on the volume up over 10MSEC.
Is this the nature of the sound or is there something else happening ?
cheers.