REW Beta Release Sound too loud to listen to when configuring sound card

Hello, I bought KH120A from Neumann and an MA1 measurement microphone from Neumann, I use REW to make my measurements because the software from Neumann does not allow measurements with the KH120A (and not the II ).

However, I have a problem during the sound card calibration settings. I hear pink noise and to reach -18db it is much too loud to be tolerated when listening. I'm not even supposed to hear it.

My settings :

Thanks !

Ok thank you, so I connect my output (left output) to input 1 (where I will plug my microphone), is that it?