HiTechObsessed :
How fast is the clicking sound? You may have something barely touching one of the fans, or a fan may be in the process of going bad. Have you opened it up to look for that yet?
yes, at one point i was turning it off and on with different combinations of fans connected and thought that my solution was that the fans were hitting a filter, so the filters gone and the sound is still there but there is nothing touching at all but dust. and it is kinda fast, not sure how fast but it is only making sound for about 3-4 seconds.