After updating to the 64-bit version of QMidi (2.8), some movie files can no longer be played.

QMidi 32-bit (prior to v2.8) relied on Apple’s QuickTime framework to read movie files. On 64-bit systems, Apple replaced QuickTime with the new AVFoundation framework, which supports only a reduced set of modern high-quality video codecs. In OS X Mavericks through macOS Mojave, QMidi could still convert eligible files into a readable format using the "QT Modernizer" Apple tool. Since this tool is no longer available on macOS Catalina, third-party software must be used to "modernize" these videos.

See also: If QuickTime Player converts legacy media files before playing them - Apple Support

I have some old CD+G Karaoke discs. QMidi will play the audio tracks but no video, is there anyway I can get the video to play?

QMidi cannot currently display CDG graphics directly from CD+G disks. You need to "rip" your CD+G disks by using the free CDGBackup software. This operation will extract your tracks as MP3+CDG files, which in turn will be played flawlessly by QMidi.

I just tried to put in my registration code to my new copy of QMidi and it says:  "either the code is invalid or it doesn't match the name".  Could you please help?

Be sure to use the right version of QMidi:
If your serial starts with "QMDP", download the PRO version, else download the standard version:

NB: To prevent confusion, be sure to remove the wrong version from your HD before entering the registration code.

On OS X 10.9 and later, when I go full screen on my second monitor the menu bar is always present. Any ideas on how to remove it or auto hide it?

The "solution" to this issue is to uncheck "Displays have separate Spaces" under System Preferences -> Mission Control.

The Transport panel is stuck in the upper left corner of my screen. The move target (left side of transport) is offscreen. How can I move or reset its location?

Hold down the shift key while launching QMidi to reset all windows positions. See: QMidi Help > Shortcuts.

QMidi does not launch/crashes on startup

  1. Download the latest version of QMidi / QMidi Pro.
  2. Restart your computer.
  3. Open the terminal and type the following lines:
  4. rm ~/Library/Preferences/com.mixage.qmidi2.plist
    rm ~/Library/Preferences/com.mixage.qmidipro.plist
  5. Launch QMidi

MIDI Playback with the Apple DLS Synth is very quiet on Mac OS X 10.7 Lion (*)

Starting from version 2.0.4, QMidi allows you to save the DLS synth volume "compensation" (offset) in the music device setup window. You can boost the volume as needed and save your changes by clicking the "Save Preset" button:

(*) On Mountain Lion (10.8), Apple has fixed this bug.