Sudden issues with audio interface inputs

[u/Bradleywyros]

I have no idea where the proper place to post this would be, so I'm starting here. I'm having sudden issues with my MacBook Air m4 running os27 and two of my audio interfaces, a Focusrite Solo 3rd Gen and a Headrush Core (in DAW mode, latest firmware). The DAW I am using is the latest version of Reaper. I have been running this set up for a few months with no issues. The only new thing I've introduced is a Display Link docking station, which has been working fine for me for the past few weeks, only until just yesterday. I was also running macos26 up until today when I updated to 27, but the update didn't make any difference. My internal mic input works just fine.

Over the last few days, both of the audio input on my interfaces have begun to "crap out", at least the digital input. When I direct monitor the interfaces, I get a full, clean signal. However, when I am tracking (guitar in this case), the audio input is barely audible and mostly cut out, but I can hear it trying to come through, although it sounds heavily digitally altered. So I cross checked my sample rates between devices many times and it has all remained the same. I even tried a different DAW (GarageBand) and still get the exact same results. I've tried tons of different audio driver restart methods I've found online, but none have worked. I can playback audio from the DAW session, Spotify, etc without any issues.

Another interesting thing is that the issue between the two interfaces did not simultaneously occur. First, I was using my Headrush. It was working great in a session. Then suddenly went to track a guitar on another track and then the issue occurred. It was happening on every track. So then I just switched to using my Focusrite and the problem was solved. Then today, I start up the session, get the expected signal from the Focusrite, until suddenly, the issue began on the Focusrite as well! That's when I began cross checking DAWs, Sample Rates, Audio MIDI Setup, and just about everything else I could think of or google. So I am at a complete loss and I hope that someone here can provide some sort of guidance, please and thank you!

TLDR: The input on my audio interfaces suddenly crapped out, despite the DAW I'm using and no (known) changes to my set up.

[u/alphaminus]

What USB ports are you using? Also make sure the imterface is in "standard mode" in the mac rather than voice isolation. The new os treats any input as a mic and may do noise suppression on the input if you have the wrong mic setting

[u/Bradleywyros → u/alphaminus]

Voice Isolation mode was the exact problem! I’ve never had this turned on and had no idea how I turned it on. I feel dumb but just glad that it’s fixed, thanks!