[Wayne A. Pflughaupt]

Here’s a cut-and-paste from my “REW quick instructions” note that I refer to when I use REW (I tend to forget the details when I don’t run it for months at a time). Comparing the settings in the pictures you provided to my notes, I’ve bolded a couple of things I see that are different. Try these changes and see if it helps.

Set the Wave Volume at 1.000 and the Output Volume about ~0.500.

Adjust your receivers volume control so the actual standalone Radio Shack SPL meter reads ~75db at the listening position.

Then adjust REW Input Volume to end up with -12dB on the REW input VU meter (i.e., matches the Output meter).

Regards,
Wayne