LMMS need to be restarted afer un/replugging midi device

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When using LMMS and my USB midi master keyboard is removed and reconnected, it is still selectable as midi in, but I need to restart LMMS to get it to work again. Not handy. Maybe an reinitialize function can be added?
Perhaps you need to provide more detail about your system and what is happening.

My computer: Macbook Pro 13 inch Late 2011 with MacOS Sierra 10.12.6
My MIDI keyboard: AKAI APC Key 25
My LMMS: LMMS 1.2.0 rc7

Instrument/plugin and preset used: ZynAddSubFX with DX Rhodes 3 preset (most likely this part makes no difference).
MIDI settings: select APC Key 25 as MIDI input / plus map VOL to first control knob on the device

Test audio and then disconnect the USB to the MIDI keyboard
Wait 10-20 seconds and then reconnect.

The keyboard is still mapped to MIDI and the audio volume can be controlled by the first control knob on the keyboard. No need to restart LMMS.

The only thing that is "lost" is that the keyboard forgets if I previously selected the Octave-Up or Octave-Down switch and that is because the keyboard is USB powered.

Edit: I tried repeating this with LMMS 1.1.3 on a Debian 9.6 Linux amd64 desktop pc with Z77 chipset and ALSA sound (all other LMMS parameters the same as before) and I also lost the MIDI connection after reconnecting the cable.

However, just like with macOS, there is no need to restart LMMS in debian linux, just reconnect the MIDI channel in the instrument settings or restore instrument settings (including MIDI) from a preset.

Some suggestions, upgrade to LMMS 1.2.0 rc (latest) and try different USB ports, e.g. USB2 vs USB3.
My setup: Windows 10 x64, Alesis Q49 usb/midi keyboard/controller. LLMS 1.2.0-rc6
Midi settings: Midi interface WinMM midi

When I assign the keyboard to a any type of track, you see it selected. Then unplug keyboard, in the track it is still selected.
Re-insert keyboard and no midi data is transferred. Need to restart LMMS.

Or when I startup LLMS without keyboard connected and then connect the keyboard, It is not available to select.
Sander wrote:
Wed Feb 13, 2019 10:40 pm
when I startup LLMS without keyboard connected and then connect the keyboard, It is not available to select.
I believe that is how it does function. It is also written in the guide for using MIDI-HW, that the sequence of connecting is important. Your wish for a 're-connect'-button is understandable, but oth restarting LMMS is not a big deal, and you should definitively restart your computer every day -eg not sleep it!!!


Besides that, since you are new in Forum
Welcome Sander !
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