Why sustain messages continue after releasing a pedal

You lift your foot, but your instrument keeps sustaining notes, or the MIDI activity display keeps showing pedal messages. The cause could be a pedal that is still sending an “on” value, a stream of changing values that is normal for that controller, or software that is holding the notes.

Test the pedal outside your music app first. The MIDI Test displays messages from a connected MIDI device, so you can see what arrives when you press and release the pedal.

Check what the pedal sends

1. Connect the MIDI keyboard or controller with the pedal plugged in. Open the MIDI Test in Chrome or Edge on a computer. MIDI Test does not work in Safari.
2. Allow the browser to access the MIDI device if it asks. If you have more than one controller connected, make sure you are watching the device with the pedal attached.
3. Leave the pedal untouched for a few seconds and watch the incoming messages. Note whether messages appear while your foot is off the pedal.
4. Press the pedal once, hold it briefly, then release it fully. Watch for the message that arrives at each action, especially the final value after release.
5. Repeat the press and release several times, pausing between each one. This helps you tell a consistent release message from other MIDI activity.

A common sustain message is MIDI Control Change CC 64. Under the standard MIDI convention, values of 64 or higher mean sustain is on, while values below 64 mean it is off. A simple pedal often sends 127 when pressed and 0 when released. Some controllers use other values, so focus on whether the final value crosses below the on threshold.

What the result means

The release value drops below 64

The pedal is sending an off value. If notes still sustain in your instrument, the problem is more likely in the music app, instrument, or another MIDI input. Check whether the app is receiving another sustain message on a different channel or from another connected controller.

The value stays at 64 or higher after release

The controller is still reporting sustain as on. A polarity mismatch, a pedal that did not return fully, or a faulty switch or cable could be responsible. If the value changes when you press but does not drop when you release, start with the pedal's polarity and connection.

Values keep changing while your foot is still

Some pedals or controllers send a range of values rather than one simple on/off pair. This can be expected for a continuous pedal, but values that jump around while the pedal is stationary can point to a loose plug, a worn sensor, or an unstable connection.

Messages continue, but the values are below 64

Repeated messages do not necessarily mean sustain is stuck. A controller may keep reporting its current position, including an off value. If the instrument releases notes normally, the ongoing messages may be harmless. If it does not, check the app's MIDI input and any other connected devices.

No release message arrives

If a press produces a message but releasing the pedal produces nothing, the pedal or controller may not be registering the change. If neither action produces a message, check that the right MIDI device is connected and selected before assuming the pedal is broken.

How to fix it

1. Check that the pedal returns fully. Remove your foot and make sure nothing is holding the pedal down. Press and release it slowly, then check whether the final message changes.
2. Check the polarity setting. Some sustain pedals have a polarity switch. Others detect polarity when the keyboard powers on. Turn the keyboard off, connect the pedal, and turn it back on with your foot off the pedal. If there is a switch, try the other position and test again.
3. Reconnect the pedal. Unplug the pedal from the controller, inspect the plug, and push it firmly back in. If it uses a removable cable, try another compatible cable. Avoid forcing a plug into a socket that does not match.
4. Check the controller or music app settings. Look for pedal assignment, polarity, calibration, or MIDI input settings in the controller software or the app that receives the messages. Windows 11 has no standard system panel for pedal polarity, so check the controller's own software or the app's MIDI settings. On macOS, open Audio MIDI Setup › Window › Show MIDI Studio to check whether the device appears, but use the controller software or music app to change pedal behavior.
5. Test without the music app. Close programs that use the controller and repeat the browser test. If the release value is correct in MIDI Test but notes remain sustained in one app, check that app's MIDI inputs and instrument settings.
6. Restart and test with another connection. Restart the controller and computer, then test another USB port if the controller connects by USB. This can clear a device connection that stopped updating correctly.

When the pedal or controller may be faulty

Try the pedal with another compatible keyboard or MIDI controller, if one is available. If it still sends an on value after release, or its values jump while it is untouched, the pedal, cable, or internal sensor may be worn. If a different pedal works reliably in the same controller, replace the faulty pedal or cable. For a built-in pedal or a controller still under warranty, contact the maker or a repair shop rather than opening the unit.

Why a stuck sustain note can outlast the pedal message

A sustain pedal does not keep sending each held note. It tells the instrument to let notes continue after their keys are released. If the instrument receives the pedal-on message but misses the pedal-off message, notes may keep ringing even after you lift your foot. A later off message may not reach the same MIDI channel, or the app may have received it from a different input than the one that turned sustain on.

When the pedal test shows an off value but the sound continues, use the music app's MIDI reset or all-notes-off command if it has one, then check that the same MIDI input and channel receive both pedal messages.