Hardly audible FIFO channels in Yu-Gi-Oh! Dungeondice Monsters (GBA)

[Dy570pia]

Music tracks sound different, and some sound effects are either muted or not properly played.

I've run the game on mGBA, manually unchecked the FIFO channel (the A one, not B), and got the exact "incomplete" audio.
However when checking SkyEmu's stats, there is an audio "output" from FIFO A, but it is extremely weak.
Using an official GBA bios on SkyEmu does not change anything unfortunately. FIFO channels are active during the GBA jingle, but happen to be still exceedingly low in the game.
Finally, I've noticed that after playing the game for a little while, the FIFO channel B increased its audio activity, as if trying to properly play sound effects (dice unfolding sounds, monster roars, etc.).

I will be providing additional info such as screenshots, screen record eventually, save file if needed, etc.; however, the bug requires nothing for it to occur, the FIFO channels are just super low from the start.

[Dy570pia]

I've noticed that a certain attack causes an output spike in FIFO B, but the sound effect sounds like the crispy creaking of a wooden door, funnily enough.

[Dy570pia]

This audio issue is exclusive to the US and European versions of the game; for a reason, the Japanese version's audio makes perfect use of both of its FIFO channels.