Trouble with MIDI output

• Sep 1, 2020 - 18:37

Working with MuseScore 3.5.0/Windows 7

For certain projects I would like MuseScore when playing a score to output to a MIDI device.

On preferences>I/O I take the MIDI output dropdown and select one of my MIDI-accessed synthesizers. If I close Preferences, then reopen Preferences>I/O, I do not see that selection in the MIDI output field.

And when I play the score, there is no MIDI output to that device.

What am I missing here?


Stay safe.

Doug Kerr


In reply to by mike320

Hi, Mike,

Thanks for that lead. I have run into this sort of things in many parts of many programs.

But I tried every variation on that theme I could think of with no result.

By the way, after I select a MIDI out device the apply button is lit.

An interesting side issue is that on the Advanced tab I can see that io/portMIDI/outputDevice in fact shows the name of the selected MIDI output device.



In reply to by Marc Sabatella

Hi, Marc,

Yes, I tried various things in that vein but with no success.

After perhaps changing other things on the dialog as well as setting a MIDI In and MIDI Out device, If I close the dialog and then re-open it, there are no entries in the MIDI In or MIDI Out fields.

I will play some more.



In reply to by Marc Sabatella


Again, it is interesting that, as seen on the Advanced tab of the Preferences dialog, if I have (apparently unsuccessfully) tried to set a MIDI In or MIDI Our device, the entries io/portMidi/InputDevice and io/portMidi/OutputDevice both show the devices I attempted to set in the I/O tab.

Nevertheless, I have confirmed that both MIDI input and MIDI output are seeminmgly inoperative.


In reply to by Marc Sabatella

Today I discovered that under the proper conditions MuseScore will in fact output to a MIDI device.

That MIDI device must be listed in Preferences>Advanced:io/portMIDI/outputDevice. This will happen if that device is set in Preferences>I/O:MIDI Output and MuseScore is closed.

If that MIDI device is not being accessed by any other application, and I start MuseScore, and open my test score, and wait for CPU activity to cease (which take quite a while - I have always assumed that this is while Fluid is being initialized), then If I click on a note in the test score (so it will sound), both Fluid and the selected MIDI device sound the note.

But this will not work with all my MIDI devices. So I need to do some more investigation.

I suspect this is some sort of problem with MuseScore not being happy to work into the same device as another app, even though the device has a "multiple-client" input port. I had a long and tedious experience with this sort of thing in Overture 5.



In reply to by Doug Kerr

Well, it seems that having no other application accessing the MIDI device when MuseScore is started is not a requirement.

So I'm not sure just why I was unable to get the output to a MIDI device to work before.

There is one MIDI device I cannot get to work (LoopBE, used to lead the output of an app to my MIDI monitor), but I will keep looking into that.


I have the same or similar issue. I turn on my Yamaha DGX-660 and connect it to my laptop. I launch Musescore. Sometimes when playback happens on the Yamaha; sometimes it doesn't.

When checking preferences, I get this screen which shows the midi devices blank. If I choose Yamaha grand and apply it, it doesn't "stick."

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