External MIDI Devices not obeying master volume slider

[Mug of Bro]

I found a bug while testing GZDoom v4.4.1, and rather than posting again in the release thread I figured I'd outline it in a place where it belongs.

When using an external MIDI solution (such as OmniMIDI or VirtualMIDISynth) I noticed that the playback volume did not reflect the master volume slider on launch of the sourceport.
While it can be remedied by adjusting the slider again or using the Windows Volume Mixer, it would obviously be more ideal if it worked as intended.
This bug also does not appear to be a result of the recent major update, as it was in fact plaguing previous versions of GZDoom despite my claim in the other thread.

Steps to reproduce:
Set master volume to 0.05
Change MIDI device to OmniMIDI or VirtualMIDISynth
Close and relaunch GZDoom
The title screen music should now be very noticeably louder than the menu and sound effects.

[Graf Zahl]

This is because the master volume slider only affects the internal sound playback - those external devices are independent of it.

[Mug of Bro]

If that is the intended behavior, why does the independent music slider adjust midi playback on relaunch of GZDoom and not the master one?
I find it a bit of a strange inconsistency.

[StroggVorbis]

Just chiming in to report that (at least for me) this also happens with the Microsoft GS Wavetable Synth on v4.4.2