[Unity/CoreSystem] Can not play 2 sounds simultaneously

I’m using FMOD 2.01.05 and currently making rhythm game using external files.
(meaning reading files outside FMOD Studio event, Unity asset path or streaming assets folder)

Here’s code I wrote for managing FMOD and sound play, using as singleton

Code Here (GitHub Gist)

Problem occurs when I play game in play scene.

When I push a button, it plays key sound correctly. But I also want to play clap sound to support players. but when i try to play clap sound along key sound, unity crashes with no error log.

Here’s code for that.

if (!btnPushSound[line])
SoundControllerFMOD.Instance.PlayKeySound(cnote.Wav, bms, cnote.Line, Const.VolumeKeySound);
SoundControllerFMOD.Instance.PlayHitSound(); // → this line makes crash
btnPushSound[line] = true;

Please refer to GitHub Gist link for PlayKeySound() and PlayHitSound() method.
How can I resolve this problem?

p.s. I tried to move to 2.02.11, but it does not load key sound files when loading games with my existing logic…
(you can find it with Gist link, preload~ named methods)
that’s why i’m staying with 2.01.05


Thank you for all the information. Would it be possible to upload a copy of the FMOD Studio Project with Banks included?

To upload to your profile, you will have to register the project with us.
As well as the Unity Project or a stripped-out version that is experiencing the issue uploaded to your profile? Without being able to step through the code myself I am unsure what the issue is.