What is your XLR output set to on the MixPre-D? Mic, or line? Whatever your mixer's output level, the recorder's input level should be set to match. If you feed a line-level output to a mic-level input, you can risk damage to the recorder.
Thanks Alex! Yes, I realized my answer. I had been doing it correctly, but for some reason was thinking there was a chance I was selecting something wrong.
*I have the output on the mixpre on line-level and line-level also selected on the dr40.
