If troubleshooting cannot solve your problem, please don't hesitate to report an issue.

1. I can't hear anything!

  1. Check current audio driver in the option dialog. Do not use an audio driver that is not installed on your system.
  2. If no soundfont is loaded, the internal synthesizer won't make any sound...
  3. Check audio driver/buffer settings in the synth section.
  4. Check if your midi file is valid/having correct bank selecting method/having zero volume.

2. The playback is intermittent.

Try increasing audio buffer size and/or audio buffer count in synth options.

3. MIDI timing is messed up.

This is a known issue under Windows. Try decreasing audio buffer size and increasing audio buffer count. Also make sure you are not using shitty cabling if you are using external synthesizers.

Also also, if you overload your computer (fluidsynth) or synthesizer too much, don't expect the timing would still keep up!

4. Some files cannot be played.

5. Some soundfonts cannot be loaded.

Files names with characters unsupported by the system locale won't load correctly in Windows. This is a known issue.

6. Sound is distorted.

Try reducing the master volume.

7. Bank selecting is incorrect for the internal synth.

Change default midi mapping if necessary.

8. Bank selecting is incorrect for external devices.

Bank selecting messages are sent to external devices directly. The midi file may be incompatible with your device.

9. 3D visualization is upsidedown/rotated/black/blinking.

For those who see a rotated and blinking display, try setting Visualization-Video/Multisampling to 1 or above. If that doesn't solve your problem or you see nothing at all, please send me more details about your problem (graphics card, drivers etc.).

Devices/drivers reported to have this issue:

10. External devices connected but does not show up.

Always connect your device before launching QMidiPlayer and make sure it is not used by another application. If it still refuses to work, make sure your device is working within some other MIDI applications. If it doesn't, try reinstalling the driver, checking the cables ... even turning it off and on again?

If it works in programs other than QMidiPlayer however, you're probably facing a new bug in QMidiPlayer.

11. Tweaking the values in channel editor does nothing.

It depends. Sound modules from different vendors accept different sets of controller messages. As for fluidsynth, it relies on the modulation matrix of the soundfont. Sadly most of the soundfonts floating around on the Internet do not have modulation matrix declared.