[RM2K] Distorted music

After playing a certain map in my game most of the songs start sounding distorted on my other maps. It's not the song that I'm using on the map that causes the issue, I've tried several different songs, including some that don't cause trouble on other maps in my game.
Is this a known issue with the program? Is there any way to fix this without removing the map (lol, it's required in one of the main questlines, and took ages to make xD).

Some more information:
When I end the game to go back to the title screen, then load up a new game or another game save, the same music in my game still sounds distorted. The only way it seems to fix the issue is by completely closing the game, then restarting it again.

MAJOR EDIT: After playing around with some new maps, and testing out things, it seems every time I change to another map now it start distorting songs. I'm assuming a complete re-install will solve the issue?
Edit: Re-install did nothing...

2nd MAJOR EDIT: It seems to happen with certain songs following up each other. Seems like a complicated issue...=/
Anyone care to try the song Interlude ingame, then change back to any other standard RTP song?

I noticed some MIDI files have no tempo set, or have various tempos. For example, one Final Fantasy pack had Chocobo Races and Clash on the Big Bridge. The latter has an unusual silence at the beginning, and if you switch to Chocobo Races(which has no fixed tempo) during this silence it becomes insanely fast.

I noticed some MIDI files have no tempo set, or have various tempos. For example, one Final Fantasy pack had Chocobo Races and Clash on the Big Bridge. The latter has an unusual silence at the beginning, and if you switch to Chocobo Races(which has no fixed tempo) during this silence it becomes insanely fast.

I google'd around some, and it appears to be a common problem in RM2K and RM2K3. This patch does a pretty good job at fixing almost all of the sound issues with the program.