For your air leaks ,#1 Take one of your grills off,Now your grills are held on with pegs that go into rubber grommets in several locations,#2 Pull one rubber plug out with your fingers,most are just loose,#3 Place one hand to the rear, and push in and out on the passive rad,Place your big face in front of the little hole you see where you removed the grommet,BINGO-- see the air that you lost,Really the cabinet is not sealed properly because the air will just escape around the rubber plugs when you play the fortes.Klipsch should off thought about this for the passive to work better,The purpose of a passive is to have a good sealed box,Now this is a good fix so you really hear the low end from the passive ,remove the front 12" driver.get some silcone (clear) (or the yellow construction glue for the inside only),For each hole put a good amount on the end of your finger,go into the cabinet and cover each hole,make sure you look in the hole on the outside to make sure you did,Now, the plug will not go all the way to the end on the inside when you insert it,now for each plug put a little silicone around each one and push them in.take your time and you will do a nice job so you dont have silcone squeezing out,Let dry for 24 and you will have a properly sealed cabinet,that is if your seals are ok behind the tweeters and drivers.Now your passive will truly work better with the front woofer.After this is done you can hear a noticable difference in low end performance.