Gesture Synth Not Working? Fix Camera, Sound, and Tracking Issues

Gesture Synth runs entirely in your browser, so nearly every problem comes from the browser environment rather than the instrument itself. The three causes that account for most reports are: a blocked camera permission, audio that has not started because the browser requires a user interaction first, and a webcam that is already in use by another app or tab.

Work through the sections below in order and change one thing at a time. Testing after each single change tells you exactly which fix worked; changing five settings at once usually leaves the real cause hidden.

The browser—not the page—controls camera access. If you chose Block when the prompt first appeared, the browser remembers that decision for the site and the hand-tracking view cannot start. Open the site controls beside the address bar (the lock or tune icon), set Camera to Allow, then reload the page.

If no prompt ever appeared, do not keep refreshing. Check the browser-level camera settings and, on a laptop or phone, the operating-system privacy setting that controls whether the browser app itself may use the camera. A site setting can look correct while the device still blocks the browser.

1. Click the lock or site-controls icon beside the address bar.
2. Set Camera to Allow for this site.
3. Reload the page and start the camera mode again.
4. If it still fails, check the browser camera settings and the OS privacy permission for the browser app.

Read the full camera permission guide →Open the Camera Help page →

A black camera area usually means the video stream never started. The most common reasons are a blocked permission (see above), another application holding the webcam, or a camera that the operating system cannot see at all. Close video-call tools, screen recorders, camera utilities, and other browser tabs that might be using the webcam, then reload.

If the preview is still black after permissions and competing apps are ruled out, test the camera in a trusted local app to confirm the hardware works. Very rarely, an outdated browser or an unusual privacy extension can block media features—try a current version of Chrome or Edge in a clean profile before assuming the site is at fault.

1. Close other apps and tabs that may use the camera.
2. Confirm the camera permission is set to Allow, then reload.
3. Test the webcam in a system app to rule out a hardware issue.
4. Try a current browser without privacy extensions.

Set up lighting and framing for tracking →

Browsers intentionally block audio until you interact with a page, so Gesture Synth stays silent until you press a key, tap the screen, or click a control. If you opened the page and waited without touching anything, silence is expected behavior—make one deliberate input and listen again.

If you have interacted and still hear nothing, check the outputs in order: the browser tab is not muted, the system volume is up, and the sound is routed where you expect (Bluetooth headphones and speakers can silently capture the output). Gesture Synth creates its sound with synthesis and does not need microphone access, so a microphone permission is never the cause.

1. Press a key or tap the player once to satisfy the browser audio rule.
2. Check the tab mute control, system volume, and output device.
3. Try keyboard mode to confirm the music engine produces sound.
4. If keyboard mode is silent too, test another audio page to check the device itself.

Hand tracking depends on a clear view of your palm and fingertips. Backlighting turns your hand into a silhouette, motion blur hides finger separation, and a busy background makes gestures less distinct. Sit about an arm’s length from the camera, face a soft light source, and keep your whole hand inside the frame.

Make one clear gesture at a time and hold it briefly. Rapidly switching finger counts is harder to recognize than deliberate changes, and a closed fist should be a full, unambiguous fist. If recognition starts well and later becomes jumpy, pause for a moment rather than waving faster—the tracker recovers more reliably from stillness.

Follow the full tracking setup guide →See the gesture and chord reference →

Keyboard mode is the fastest way to find out where a problem lives. It plays the same styles and chord progressions without any camera input, so it separates the music engine from the camera path. If keyboard mode plays sound and responds normally, the instrument is fine and the issue is in permission, lighting, framing, or a competing app.

Keyboard mode is also a practical fallback while you fix the camera. Many players use it permanently on shared computers or in places where enabling a webcam is not appropriate.

Play in keyboard mode now →Learn the keyboard playing method →Browse all guides →