Midi Keyboard Not Transmitting to Reaper, but Midi Pad Does?

Support & Troubleshooting
1
  1. Summary / Title

MIDI Keyboard object does not send MIDI to Reaper, while MIDI Buttons work correctly

  1. Steps to Reproduce

Step 1: Connect MetaGrid Pro to Reaper via MetaServer. Confirm the connection is working.

Step 2: Create a button in MetaGrid Pro that sends a MIDI note.

Step 3: In Reaper, arm a track and set the input to All MIDI Inputs.

Step 4: Press the MIDI button. Reaper immediately receives the MIDI and shows MIDI activity.

Step 5: On the same MetaGrid Pro grid, add a MIDI Keyboard object.

Step 6: Play notes on the MIDI Keyboard object (regardless of which MIDI channel it is set to).

  1. Expected Result

The MIDI Keyboard object should send MIDI note data to Reaper just like the MIDI button does, and the armed track should display MIDI activity and receive the notes.

  1. Actual Result

The MIDI Button successfully sends MIDI to Reaper every time.

However, the MIDI Keyboard object sends no MIDI at all. Reaper shows no MIDI activity on the armed track, regardless of which MIDI channel the keyboard is configured to use. Changing the MIDI channel does not affect the behavior.

No error messages are displayed.

  1. Screenshots or Video (if applicable)

None currently, but I can provide screenshots or a screen recording if that would help diagnose the issue.

  1. Device Information
    Operating System: macOS Tahoe (latest version)
    MetaGrid Pro version: v1.7.3
    MetaServer version: v6.1.3
    Device Model: iPad connected to Mac
    Affected software: REAPER (latest version)
  2. Additional Notes

I have already verified that MIDI communication between MetaGrid Pro and Reaper is functioning by using a MIDI Button object. Since the button successfully transmits MIDI, the connection appears to be working correctly.

The issue seems to be specific to the MIDI Keyboard object, which produces no MIDI output in Reaper under the same conditions. I’ve tested multiple MIDI channels on the keyboard object while Reaper is configured to receive All MIDI Inputs, but the behavior is always the same.

2

Just an update, I have run a MidiViewer app to log any/all midi coming into my computer and the midi keyboard/piano object does not transmit any data whatsoever.

Metagrid Pro v1.7.3
Metaserver v6.0.3 Build 6010

3

Thanks for the additional test. I have now traced the Piano Keyboard implementation in MetaGrid Pro.

Please check these points:

  1. Set the Piano Keyboard’s Velocity clearly above zero.
  2. In MetaServer, confirm that the Metasystem MIDI output is enabled or mapped.
  3. In REAPER or MIDI Monitor, select Metasystem - MIDI - In explicitly.
  4. Please also tell me which MIDI destination is selected for the working MIDI Button.

The Piano Keyboard always sends through the Metasystem MIDI destination, while a normal MIDI Button can be assigned to a different destination. This means the button can work even when the Piano Keyboard’s destination is not currently available.

Please also confirm whether the computer is running macOS or Windows, and the exact MetaServer version, as the two posts contain different environment details.