SFX echo in battle

[qwertymodo]

When using the resume version of the patch and supplying track 69 to play the MSU-1 audio during battle, the menu SFX, like changing selection, or selecting an action, as well as some other SFX like the sword, echo for a really long time. In higan v101, it just makes the sound effects sound "screechy" but on the SD2SNES, the SFX just keep ringing for a second or two. The issue does not occur with SPC fallback, so deleting track 69 makes it go away. It only occurs when the MSU-1 is playing in battle. I have not tested the non-resume version of the patch.

[qwertymodo]

After having trouble replicating it, I finally was able to make it happen again, but not consistently. I'm just at the very beginning of the game, wandering into the woods instead of going to the fair, and fighting those few battles there over and over. Eventually, the echo starts happening, and then it continues pretty consistently for the rest of that play session.

[qwertymodo]

Here's a video demonstrating it. See 0:11 and 0:36

https://youtu.be/fWAhNvTvoFo

Edit: An even more prominent example:
https://youtu.be/VWDL5rVK-Jo

[qwertymodo]

I think it might be related to the subroutine MSU_BattleSampleHack, because it executes for battles where the SFX are correct, but when the echo starts happening, it doesn't execute anymore.

[qwertymodo]

One way I have found to reliably trigger the bug is to go to the Hunting Range and just wait for the rain, then enter any battle before leaving (including the Nu).

[qwertymodo]

Doing some more digging, it seems like when the game tries to execute command $14, you need to mute the SPC using command $14 and value $00 in $1E01, instead of using command $10 with value $00 in $1E01.

Edit: Actually, it seems to just work better to always mute the SPC using command $81 with $01 and $02 both set to $00 (instant fade to 0).

[luncht1me]

Can you supply a patch for this? I've just patched my rom and the echos in the battle are kind of annoying. I'd love to have them removed. It's happening in EVERY battle for me. Or tell me how to fix it

[qwertymodo]

It's not a simple patch, at all. Interestingly enough, the problem occurs in the vanilla game as well, just far less frequently (probably the main example is the staircase full of bats immediately before fighting Magus).

I have a completely rewritten MSU-1 hack that includes FMV support over on the romhacking.net forums that has (mostly) fixed this issue, you might give that a try. NB: it is not the one on my github repo, that is just a fork of this repo with a few minor changes, and does not fix this issue.