It does get quite annoying, my favorite is in the cabin of the A320...the Hydraulic pumps make noises almost like a hand saw. I have fun with that one...."yea, they have to put a padlock on the cargo compartment, i guess the combination never got forwarded"

Just tell em it's normal, but never just brush it off..passengers can be a pretty good eye if something is really outta whack about 1% of the time..and it's that 1% that'll really save your butt. So always pay attention.

Or just feed em some "We won't depart unless your safety and the integrity of the airplane is assured"