Noob question: all my measurings look flat

hi guys,

just started today with the program.

step1:
after reading the manual, I tried to calibrate the soundcard.
output ==> directly to input (with jack)
I made the test signal check and had output and input signals.

I press "measure" and it makes the sweep. I see it on input and output.

Result: absoulte perfect line from 0 hz to 20'000 hz. I believe in Mackie but I can not imagine, that this is realistic


step2:
I calibrated the output to 75dB (with an external mic DB device). I put on a microphone into the preamp of my mackie-unit. I used the raw-subwoofer. all levels ok, sweep takes place... an absoulte linear graph as a result.


I also tried the manual sweeps.. they work great.. so I have definitly output or the program working

I am doing something fundamentaly wrong.. what is the problem?