The problem with Android is that it runs on so many different devices and they all tend to have their own (sometimes odd) preferred buffer sizes.
For minimal latency we recommend using OpenSL and the device output native frequency, leaving FMOD to handle the DSPBufferSize (defaults to 512 x 4, which then feeds the hardware at it’s native size).
Warning! The ‘buffersize’ is generally best left alone. Making the granularity smaller will just increase CPU usage (cache misses and DSP network overhead). Making it larger affects how often you hear commands update such as volume/pitch/pan changes. Anything above 20ms will be noticable and sound parameter changes will be obvious instead of smooth.
FMOD chooses the most optimal size by default for best stability, depending on the output type. It is not recommended changing this value unless you really need to. You may get worse performance than the default settings chosen by FMOD.
There is some more information on latency on Andoid devices here:
https://www.fmod.com/resources/documentation-api?version=2.0&page=platforms-android.html#audio-latency