mido: Cannot connect to MIDI device with two identical MIDI USB VID PID

I’ve two identical MIDI devices with the same MIDI USB VID and PID. One of the two devices is set into update mode and registers with a different set of MIDI input/output port names. Functions mido.get_input_names() and mido.get_output_names() returns an incorrect list of MIDI port names when both MIDI devices are connected to the computer.

Python test script:

import mido

print(mido.get_input_names())
print(mido.get_output_names())

Output:

1. Connect first device A and run test script (Correct output):
    ['MyDevice 0']
    ['Microsoft GS Wavetable Synth 0', 'MyDevice 1']

2. Connect second device in update mode and run test script again (Correct output):
    ['MyDevice-update 0']
    ['Microsoft GS Wavetable Synth 0', 'MyDevice-update 1']

Connect first device, then second device in update mode and run script again (Incorrect output):
    ['MyDevice 0', 'MyDevice 1', 'MyDevice 1']
    ['MyDevice 1', 'Microsoft GS Wavetable Synth 0', 'MyDevice 1', 'MyDevice 2']

I can open MIDI ports on MyDevice 1, but not on MyDevice-update x. Is there a workaround or do I something wrong?

Info:

Windows 10
Mido: v1.2.10
python-rtmidi: 1.4.9
Python: v3.9.10

About this issue

Original URL
State: closed
Created 2 years ago
Comments: 16 (8 by maintainers)

Most upvoted comments

Just stumbled across that: https://gist.github.com/yoggy/1485181 Maybe enough.

Thanks for your hint. Same problem with updated source. So the problem is located in the Windows API. I think research stops here:

Output (incorrect):

MIDI input devices:
    0 : name = MyDevice-update
    1 : name = MyDevice-update
MIDI output devices:
    0 : name = Microsoft GS Wavetable Synth
    1 : name = MyDevice-update
    2 : name = MyDevice-update

wMsg=MIM_OPEN

Erriez on Jul 16, 2022

I’ve built this Windows C# MIDI UWP example from source and works as expected: https://docs.microsoft.com/en-us/samples/microsoft/windows-universal-samples/midi/

Erriez on Jul 16, 2022