[iOS] Frequent SystemNotInitializedException

The only other issue I can think of is if the app is suspended/sent to the background while it is starting up (during FMOD’s initialization). To avoid this you can enable the settings for background audio which will allow FMOD to init if suspended, but will still pause the sounds due to Unity and code in the RuntimeManager.cs.

https://developer.apple.com/library/content/documentation/Audio/Conceptual/AudioSessionProgrammingGuide/AudioSessionBasics/AudioSessionBasics.html