FL itself. I use to own the MBOX pro prior to getting the steinberg UR44 and don't think I use to deal with that issue as bad, not sure what the issue may be though.
My setup is just ...
FLStudio? seems like it's something that's in every daw. I don't know why but i've always liked seeing waveforms or midi notes appearing as im recording them. anyone know if this will ever be added ...