REW bug or MOTU M4 bug

[lizhuoyin]

Just got M4 with firmware 2.00.
REW is 5.20.

I was calibrating the soundcard(M4) using REW.

You can see in the picture:
Output/1: Out 1 is M4's monitor out 1;
Input/3: In 3 is M4's line in 3;

I am confused with Out/In meter.
Is Out meter for Output and In meter for Input?

Because, if MOTU main(monitor) knob is at min position, In meter will have no color bar. If MOTU main knob is at max position, In metter will have a color bar top at around -23.8.
Out meter stays at -20.0 all the time.
It looks like In meter is for Output (M4's monitor out) since it's controlled by main knob!!! And Out meter is for input.

 

[HighImpactAV]

The Out meter is showing the output of REW, which is staying constant at -20 dB. Because you are adjusting the Monitor output on the MOTU M4 with the volume knob, this is lowering the voltage sent to to the loopback input. The In monitor is then correctly showing the lowered levels.

 

[lizhuoyin]

The Out meter is showing the output of REW, which is staying constant at -20 dB. Because you are adjusting the Monitor output on the MOTU M4 with the volume knob, this is lowering the voltage sent to to the loopback input. The In monitor is then correctly showing the lowered levels.

Thanks a lot. If Out is showing the output of REW, everything makes sense to me now.