When I open a program that uses MIDI files it doesn't load the correct preset if in fullscreen

Hello, first of all thanks for the creation of VirtualMIDISynth ^-^

The problem I have is this:

I needed better soundfonts than the default one for windows 10 for use with a game called "7th Stand User", which was created with rpg maker 2000.

I don't have the knowledge of how rpg maker 2000 works with MIDI files more than knowing it plays files in certain points in the game, like the title screen.

The bug I have found is that when the title screen midi file (and other files but not every file) plays if the game is in full screen it doesn't use the correct preset, it just uses the 0:0 preset (which is grand piano in both sound files I have found) for every channel in the mixer.
If I change the value of the preset from -1 to one I know plays in the midi file then it doesn't sound.

What is strange is that if I wait until the song ends and plays again then it picks the correct instruments for every channel, even in fullscreen.

So in summary if in full screen it only plays right the second time, if in windowed it plays correctly always.

I currently don't know more programs that use MIDI to test.

I could upload the midi files if needed and even the game as it is standalone, doesn't need install and it's lightweight.

I don't know if a solution could be found because it may well be a problem with rpg maker 2000 and support for that doesn't exist anymore, but if someone has a similar problem with a fullscreen program or knows what it could be I would appreciate any help.