If you updated OBS Studio and can no longer find Monitor Only (mute output) in Advanced Audio Properties, the feature has not vanished. In OBS 32.2, you create the same result with two separate controls in the Audio Mixer: turn monitoring on (the headphones button) and turn output off (the speaker/mute button) for that source. You hear the sound locally, while that source’s direct output is muted. But there is an important catch: if OBS also captures the device playing the monitored sound, that sound can still get back into your broadcast.

Why the old Monitor Only choice disappeared

The change happened in two stages. OBS Studio 32.1, released in April 2026, redesigned the mixer and added a button to toggle monitoring directly. The OBS 32.1 release notes also describe the new default vertical mixer layout and source-pinning controls.

OBS 32.2 followed in July 2026 and removed the redundant Monitor Only entry from Advanced Audio Properties. Its official release notes explicitly say monitoring and muting are now handled independently. Older YouTube tutorials may still point to a three-way dropdown, so searching for that missing menu can lead you in circles. Rave-Tech’s earlier OBS 32.2 update overview covers the broader release; this guide deals with the specific audio route.

What the speaker and headphones buttons actually do

Think of each audio source as having two destinations. Output sends it toward the selected recording or livestream mix. Monitoring plays it locally through the monitoring device chosen in OBS settings. The OBS Audio Mixer Guide identifies the speaker icon as the output mute control and the headphones icon as the local monitor control.

For an alert sound you want to hear but not broadcast, enable headphones and mute the speaker for that source. For a voice-chat guest everyone should hear, keep output on and enable monitoring only if you need local playback through OBS. For game audio you already hear directly through your PC or console, you may not need OBS monitoring at all.

This also explains a new surprise: pressing mute may stop a sound in the stream while you continue hearing it in your headphones. That is expected when monitoring is independently enabled, not proof the mute button is broken. If you want to silence the sound in both places, disable monitoring too.

Set up a local-only alert without creating an echo

Open Settings > Audio and check Advanced > Monitoring Device. Choose the headphones or audio interface you actually want OBS to play through. The labels and layout may vary by OS and OBS version. Then, in the Audio Mixer, find the alert or media source, turn on its headphones/monitoring button, and mute its speaker/output button.

Play a sample alert. You should hear it through the monitoring device. Make a short local recording and check that the alert does not appear in the chosen recording track. Do not rely on the moving meter: it confirms that OBS receives audio, not which destination ultimately hears it.

The second route is the crucial check. Suppose OBS monitors an alert to the same headset that your Desktop Audio source captures. Desktop Audio can pick up the alert after it has been played locally, sending it back into the output despite the original alert source being muted. That can sound like duplicate audio or make a supposedly private cue audible to viewers.

The OBS project’s Audio Sources documentation separately warns that adding a device as an Audio Input/Output Capture source while also selecting it globally under Settings > Audio can produce an echo. Avoid capturing one device twice. Where possible, keep the monitoring device out of the devices captured for the stream, and remove an unnecessary overlapping audio source rather than turning off every sound.

When the VOD is still missing or doubled

Keep three different problems separate. If you hear an alert but the live stream does not, that may be the intentional monitor-on/output-muted setup. If viewers hear it twice, inspect whether desktop capture and an individual application or device source are picking up the same audio, including monitored playback. If the livestream sounds right but the saved Twitch replay is missing game audio, investigate track assignments instead; Rave-Tech’s Twitch VOD audio-track troubleshooting guide covers that separate routing problem.

Before an important stream, record about 30 seconds with the actual game, chat, alert, and microphone active. Listen back on a second device if possible and deliberately trigger the sounds you want only you to hear. Check the selected stream and recording tracks individually when they differ. Once every sound has the intended route, preserve that configuration instead of changing several settings at once.

The fix is not to reinstall OBS or hunt for the old Monitor Only dropdown. In OBS 32.2, the speaker controls output and the headphones control monitoring. Set both deliberately, then make sure no second capture path sends your private monitoring audio back to the audience.