I see limit lights on my Yorkville LS801p, very often as well. This is while running the units at 25%, and without driving signal level much at all. It amazed me that as soon as I put a dbx166xs between the mixer/speaker that limit lights are no more. Same thing holds true for my QSC tops, Bose L1, etc. etc. My point being, when coming straight off the mixer, seems that most all powered speakers hit limit lights pretty easily.
Are you suggesting a compressor is needed and one cannot come out of a DJ mixer into powered speakers?