I have often read of the rattlesnake noise on the e-pl1, and have commented mine is quiet. And now I know why. I almost always shoot in manual mode including manual focus. A few nights ago while doing some night shots, I powered on the e-pl1 and had it on auto focus, and sure enough as the lens tried focusing while I was walking it made this rattle snake sound. So now I heard it, yet it didn't bother me, aslong as I get some good files, the lens could make a farting sound for all I care.