it's possible that this difference is due to the hardware capabilities of the two controllers. The Core2 may have a built-in audio module that allows it to play WAV files, while the Fire controller may not have the necessary hardware to support this feature.

It's also possible that the developers of UIFlow simply haven't had the time or resources to implement the "play WAV file" function for the Fire controller yet, but it may be added in a future update. You can also check different services provided by us.