Audio MIDI Setup Not Working on Mac: Troubleshooting

Identify the symptom and environment

Start by recording exactly what happens in Audio MIDI Setup on your Mac. Note the macOS version, whether the audio device is connected by USB, Thunderbolt, HDMI, or Bluetooth, and whether the problem occurs after startup, after sleep, or only in a specific app. If a USB audio interface or microphone does not appear, check whether its power light is on and whether the same device works through another port or cable before changing settings.

Open Audio MIDI Setup from the Utilities folder inside Applications. In the Audio Devices window, confirm whether the expected device is listed as an input device, an output device, or both. A device can appear in the list but still show no input level, so treat missing hardware and missing signal as separate symptoms.

Isolate where the fault occurs

Separate the possible failure points: the device, the connection, macOS audio settings, and the application using the device. In Audio MIDI Setup, select the device in the sidebar and look at the input and output tabs. If the output side works but the input shows nothing, the problem is more likely in the input path or microphone settings than in the connection itself.

Test the same device in a second app, such as a voice recording or video call tool, only when it helps distinguish an app-level selection issue from a system-level problem. If the device works in one app but not another, check that app's audio input and output device menus rather than reinstalling or resetting the Mac.

Where an app uses a browser, separate browser permission from operating system permission. A browser may block microphone access even when macOS lists the microphone correctly. Check the browser's site permission for the current page and the macOS privacy setting for microphone access.

Try reversible fixes in order

• Check the selected input device in Audio MIDI Setup and set it to the microphone or interface you want to use. Some devices expose separate channels, so try another channel only if the current one shows no input level.
• Check the selected output device and choose the built-in output or the connected interface. Audio may be routed to a device that is not currently connected.
• Look at the input level meter while speaking into the microphone. If the meter does not move, adjust the input volume slider in Audio MIDI Setup or in Sound settings without pushing it to maximum.
• Compare the sample rate for the input and output devices. Set the device to a common rate such as 44100 Hz or 48000 Hz, and make sure the app using the device supports that rate.
• Turn off any unused input device that may be capturing background noise, or select the correct device explicitly instead of leaving the app set to automatic input selection.

Menu names and settings locations vary by macOS version. In current versions, microphone and output choices can also be found in System Settings under Sound or Privacy and Security. When an older version used a different location, look for the same concept: an input device list, an output device list, and a microphone privacy switch.

Confirm the result

Return to the original app where the problem appeared and make a short recording or test call. Speak in a normal voice and confirm that the input level meter responds, playback comes through the intended output device, and the background noise is not loud enough to cover the voice. A change is confirmed only when the original symptom is gone in that app, not just because the settings look correct.

Do not jump to a factory reset or broad security change to confirm the fix. Reversible changes such as device selection, sample rate, and volume are enough to identify most setup problems.

If the problem remains

Keep a note of which device appears or disappears, which cables and ports were tested, what the input level meter shows, and whether the behavior changes after a restart or after waking from sleep. This information helps distinguish a macOS routing problem from a device fault.

Contact the device manufacturer's support or a repair service when the same device fails on another Mac or computer with different cables. A device that is not detected anywhere is a hardware suspect, but a symptom on one Mac alone is not proof that the hardware has failed.