Yasin00006
commented
9 months ago I can confirm that this an issue with Fire Emblem The Blazing Blade as well, it triggers when I move the cursor in the maps and moving units and/or progressing dialogue for some time(some minutes), I tried the fast-forward mode and indeed the issue seems to appear sooner that way. The sound effect of the dialogue scrolling gets distorted and the sfx of moving the cursor around the map gets muted with a bit of buzzing in the music. The issue is absent when using other emulators.
Summary
It's like a sort of buzzing sound (recordings below) that's not present on a fresh boot of the game, but appears after playing it for some time. It's most noticeable on the menu sound effect, but you can hear it slightly in the music too.
Here is a ZIP archive containing FLAC recordings of the "bad" and "good" (after reset) audio taken using mGBA's AV record function: mgba_audio_distortion_samples.zip
Here is the bug report ZIP file from mGBA. Loading the save state in here immediately reproduces the issue for me: mgba_audio_distortion_report.zip
Reproducing
To reproduce it, it's necessary to interact with the game for some time. Just letting the game run idle doesn't cause it to happen, even if there is background music playing.
I found that the most reliable way is to put the emulator on fast-forward mode, and run around in tall grass triggering wild Pokémon encounters then run away from the battle. Doing this for a minute or so is enough to trigger the issue.
Interestingly, it doesn't seem to happen on Ruby/Sapphire. So I wondered if it's actually a bug in the game itself, but there's no mention of it online that I could find, and I couldn't reproduce it in other emulators (sadly I don't have real hardware to test).
Settings/Environment