with author annotation
Basically I had to use after effects first.
Put the audio file in an AE composition, then right click and select "Convert Audio To Keyframes". Then you select the audio layer again, and press U twice fast. Now you can see your audio levels as keyframes.
Copy paste the key frames into a text document, then write a script in Realflow to read that text doc to import the audio.
I usually just connect it to the scale of a cube so that I can reference the scale of that cube (which is now the audio levels).
There is a way to import directly from the audio file into real flow. But that level of Python is too advanced for me.
and i'm wondering if anyone of you can write such script?