The systems reference 0 dB differently. Quickest fix is to change your meters from peak to RMS. That will get you more signal to PT. Easiest way to understand what is going on is to watch the 05/23/08 webinar on PT HD vs PT LE and the 06/25/08 webinar on Virtual Soundcheck.
http://www.digidesign.com/index.cfm?...4&itemid=31029