There’s a couple things this could be, can I get you to do the following?
- Take a screenshot of your Bank Import settings in Unity under FMOD → Edit Settings
- Take a screenshot of your “Built banks output directory” in FMOD Studio under Edit → Preferences → Build
The import settings and bank locations not lining up is the regular culprit of these sorts of issues.
I’d also recommend double-checking the location of the event in FMOD Studio in the event editor, that it’s assigned to the music bank, and that the banks are being built successfully on disk (i.e. check the last modified time). You should also force a bank refresh in Unity from FMOD → Refresh Banks to ensure that the updated music bank is being registered in Unity.
See here for how to resolve the error spam: Integration tutorial issue: AudioPlayableOutput::OnApplyFMOD: Could not get FMOD System - #2 by Leah_FMOD
This should be fine.