MIDI CC values missing after adjusting velocity curves

You adjusted a velocity curve, and now a knob or pedal seems to have stopped sending MIDI CC values. The two can affect the same performance, but they are different kinds of MIDI data. A quick check outside your music app can show whether the controller is sending the CC message at all.

Use the MIDI Test to watch incoming notes, velocity, knobs, pedals, and other MIDI messages. It runs in a browser, so you can compare the controller's output before changing more settings.

Check for the missing CC value

1. Open the MIDI Test in Chrome or Edge on a computer. The MIDI Test does not work in Safari.
2. If the browser asks to access MIDI devices, allow access. If the controller is not immediately visible, reconnect it and select it if the test offers a device list.
3. Move the physical knob, slider, or pedal that should send the missing CC. Watch for a message with a controller number and a value. Note which control you moved and whether the value changes.
4. Play a few notes at different strengths and watch the velocity values. Then adjust the velocity curve and play the same notes again.
5. Move the same knob, slider, or pedal again. Compare its CC message with the first check. Keep the same controller, preset, connection, and browser for both tests.

A key press usually sends a note message that includes velocity. A knob or pedal may send a separate Control Change message, often called a CC. If you need to identify the controller number, see how to check MIDI control-change numbers.

What the result means

The CC message appears in the test, but not in your music app

The controller is sending the message, so the velocity curve is not blocking it from reaching the computer. Check that your music app is listening to the same MIDI input and channel, and that its MIDI filters or control mapping are not ignoring that CC number. A track can receive notes while a control surface or automation input is configured separately.

Notes and velocity appear, but the knob or pedal sends no CC

The controller and browser can communicate, but that control is not producing a CC message in this test. It may be assigned to another function, set to a different mode, or configured to send a different type of MIDI message. The velocity curve alone normally changes the velocity of notes, not the messages sent by a separate knob or pedal.

The CC number appears, but its value stays the same

The control is sending something, but its position may not be changing the value. Check whether the control is configured as a switch with only two values, whether it is already at an endpoint, or whether the device has a custom assignment. A pedal may also need calibration in the controller's own settings.

No MIDI input appears at all

The browser is not receiving messages from the selected device. The controller may be disconnected, unavailable to the browser, or connected through a port that is not the one you are using. Reconnect it and check again. If the browser permission was denied, change the site's MIDI permission in the browser settings and reload the test.

How to fix it

1. Test the control that should send CC. Move a knob, slider, or pedal assigned to a CC, rather than relying on key presses. If you expect a key to send CC, confirm that the controller has an explicit mapping for that behavior.
2. Check the control's assignment. In the controller's configuration software or onboard settings, confirm the control sends a Control Change message and check its CC number and MIDI channel. A velocity curve setting usually changes how hard or softly notes are reported, not the CC assignment.
3. Confirm the input in your music app. Choose the same MIDI device or input port that appeared in the test. Check the app's MIDI input and control-surface settings. Menu names vary by app, and Windows 11 and macOS do not provide one universal system page for assigning a controller's CC numbers.
4. Check for channel or message filters. Set the controller and receiving app to the same MIDI channel, or temporarily accept input from all channels. Turn off CC filtering or learn-mode restrictions while testing, then restore your normal setup.
5. Save and reload the controller preset. If the issue began after editing a curve or preset, save the intended configuration, reload it, and verify that the CC assignment remains in place. Avoid resetting the device until you have recorded custom assignments.
6. Reconnect and test another port. Unplug and reconnect the controller, then test it directly on another USB port if possible. A different cable or computer can help separate a connection problem from a controller configuration problem.

When it's the controller

If the same control sends no CC in the MIDI Test on more than one computer, while other controls on the device work, the problem is likely its assignment, preset, or hardware. Check the device's documentation for how to restore or configure that control. If it still produces no message after verifying the assignment and testing another connection, contact the manufacturer or arrange a repair. A browser test can show what reaches the computer, but it cannot diagnose a failing internal switch or pedal sensor.

Why velocity and CC can seem connected

Velocity is a value attached to a note event, often affected by how firmly or quickly you press a key. A velocity curve changes the relationship between your playing force and the velocity value sent. CC messages are separate events used by knobs, sliders, pedals, and other controls. Some controllers let you map a control to a CC, but changing the key velocity curve does not normally change that mapping.

The MIDI Test works in your browser, and Safari is not supported for this test. If a message appears there but not in your music app, focus on the app's input, channel, and filtering settings.