Hi, my sound card is a cheap Steinberg UR12. It has just two outputs: monitor L and monitor R.
Following the instructions that appear on the screen in the profiling process I connected the Monitor L output (RCA) to the input of the reamp box (XLR). Having connected everything else as as indicated in the instructions I do not understand why the profile of my amp is so incorrect. The only weak point seems to me to be the output of the sound card. I use an iMac M3, a passive Palmer reamp box and a SM57 microphone. Thanks.