Macbook Air laptop mic is always on when measuring with my 711 coupler. How do I turn it off?

[mucklechumps]

I am using REW 5.40 on a 2025 Macbook Air A4 running Tahoe 26.3, but this issue has been a problem for me with older OS and REW builds. I have a 711 coupler that requires phantom power so it goes into an Audiomatica PRE01 preamp, out of that and into a MOTU M2, then out of that and into my laptop via USB C. I can't seem to disable the onboard laptop mic. If I go into privacy settings on my mac and disable the laptop microphone for REW, the 711 doesn't work. And if I go to Mac Sound settings and select the M2 for both input and output, I get the orange mic icon on my top panel and I can't turn it off.
The laptop mic is definitely picking up audio when I make an IEM measurement with my coupler. Both the 711 AND the laptop mic are engaged. I feel like I've tried everything to fix this. Any ideas? Thanks!

 

[Sonnie Parker]

I have a MacBook, and it's a bit different from my PC. Make sure REW is actually set to use the MOTU M2 as the input device (Preferences → Soundcard), and that you’re not using an aggregate device in Audio MIDI Setup (cmd+space and type Audio MIDI and open that app - you'll see all the mics listed). The orange mic icon just means a mic is active... it doesn’t necessarily mean the MacBook mic is being used.

 

[John Mulcahy]

In macOS "microphone" is used to describe any audio input and the mic symbol is shown when any audio input is being used. REW only uses the selected input.

 

[mucklechumps]

I have the M2 set as my input device, and midi shows my M2.
John, when I am on the "measure" screen and I lightly tap the mic on my laptop, I see the levels bounce on the input display, and I see the levels also bounce on the input of the Motu M2. The 711 coupler mic is in a sound proof box and is definitely not picking up the tap on the laptop mic. The 711 is ALSO active and when I tap on that I see the levels bounce on both the REW input display and the M2.

 

[mucklechumps]

I think I figured it out and I feel kind of stupid. I have the 711 coupler in a sound isolating enclosure but the whole thing, including my laptop, is on a folding card table and I believe even the light taps on my laptop are resonating through the table and through the enclosure. When I lift my laptop off the table and tap the laptop mic, the levels do not bounce. I'm going to put the test rig on a more substantial table and try again. Thanks for the help John and Sonnie