couple of things to check. first, make sure in control panels-> system-> advanced-> performance you have background services checked, and not applications. second, obviously have the latest drivers for both your Delta 44 and MOTU MIDI interface installed. As long as you do both of those things and have the Delta 44 -> ASIO selected under Reason preferences then you shouldn't have the latency. do you have any other progams open along with Reason, even things that don't show up in the taskbar/system tray? or are you using a mac?
= chiisu