Help needed - Calibrating Audio Interface - feedback loop - Steinberg UR44C, Windows 8.1, REW 5.20

[sonorman]

Hi,
I'm new to REW.
I'm trying to follow the Soundcard Calibration instructions in the REW Guide and also this video from GIK Acoustics:

As I understand it, I need to connect a cable directly from a LINE OUT to and LINE IN on my UR44C interface.
I have tried all possible combinations, but according to the REW Guide, Section "Calibrating your Soundcard", Point 5, I must have a feedback loop.
Every combination produces a terrible, loud, piercing noise.

Can anyone tell me what I am doing wrong?

I cannot find any setting in the Steinberg driver to turn off "monitoring" for the UR44C.

These are the UR44C IN/OUTs:

This is the example from the GIK Acoustics REW Tutorial video:

 

[sonorman]

Following on, if a microphone is connected to the XLR port on an audio interface that is connected to the PC via USB, is the non-USB mic considered as a USB mic for the purposes of calibration?

Under "Calibrating the Soundcard" in the REW Guide, it clearly states:
"This step is not applicable when using a USB microphone as the input, skip directly to Check Levels."

 

[John Mulcahy]

if a microphone is connected to the XLR port on an audio interface that is connected to the PC via USB, is the non-USB mic considered as a USB mic for the purposes of calibration?

No.

 

[John Mulcahy]

according to the REW Guide, Section "Calibrating your Soundcard", Point 5, I must have a feedback loop.
Every combination produces a terrible, loud, piercing noise.

Speakers shouldn't be connected when calibrating the soundcard, just soundcard output to soundcard input. From the UR44 manual it looks like direct monitoring is turned off using dspMixFX or va Cubase if you use that. If you use the ASIO drivers to access the card monitoring should not be active, but you might still need to turn off direct monitoring.

 

[sonorman]

Speakers shouldn't be connected when calibrating the soundcard, just soundcard output to soundcard input. From the UR44 manual it looks like direct monitoring is turned off using dspMixFX or va Cubase if you use that. If you use the ASIO drivers to access the card monitoring should not be active, but you might still need to turn off direct monitoring.

Thanks so much for your very kind advice. I will try your suggestion and post the results here.