getNumDrivers returns "NoDevice" after re-plugging last device

[li_fmod]

Hi,

Thanks for sharing the code and logs.

Since Connor is away, I will continue with this support case.

I was able to reproduce this locally with a minimal Unity test. When the DEVICELISTCHANGED callback is registered, FMOD reports NoSound Driver after the last device is disabled, and it does not automatically switch back when the device becomes available again.

This matches the behavior described in the documentation:
https://www.fmod.com/docs/2.02/api/troubleshooting.html#my-audio-device-does-not-change-automatically

In this case the application needs to handle the device change itself (for example by selecting a driver again or reinitializing the system). If the callback is not registered, FMOD will normally handle device switching automatically.

There is also a related discussion here about handling device changes on Windows:

FMOD.System.getDriver is unreliable after the default device is changed on Windows

This behavior is a result of registering for the FMOD_SYSTEM_CALLBACK_DEVICELISTCHANGED callback, which overrides the default behavior. The value returned from System::getDriver is only updated when calling System::setDriver and by overriding the FMOD_SYSTEM_CALLBACK_DEVICELISTCHANGED callback, FMOD no longer does this automatically, you will need to handle this in your callback.

Hope this helps!