Here is a quick video showing my tumbling. The video doesn't convey how loud it is but I can hear these things rattling and pinging off the reactor cylinder upstairs in bed.
http://www.youtube.com/watch?v=-LT1v_OR_Ac
Reducing flow makes it quieter but still not great but I have no valve yet can only pinch the hose.
I should note that I did Kevin's 'red coral mod' and simply took out the bottom red plate so water just exits the tube. Maybe that is related to the noise I'm not sure?