This may be a really noob question, but aren't the recording levels tapped off the same preamps as the main output? There really shouldn't be such a big difference between the two. Usually on an analog mixer the line outs (and RCA stereo outs) should receive the same signal levels as the main outputs? Yes, there is usually, but not always a physical level control on the RCA (record) and line outs.
It's not a big deal for me particularly, since if I need to do a quick recording session I can use the main outs to an external USB recording device to my laptop, running my DAW etc. etc. etc.
If I am totally out in left field with my assumptions, I stand (or sit) corrected and would really appreciate being educated on this particular issue with the DL.