if i understand it correctly, the maximum frame rate is 120 fps, which is more than enough for video, but if you’re are going to include some more audio stuff (e.g. VST, DirectX plugins) it’s not always sufficient. also the frame rate is not fixed, does this mean that it is impossible to do some beat accurate stuff (without hearable jitter)? (e.g. one could send control data to some audio software like Pd, Max or Reaktor).
if you create a MainLoop node you can set the frame rate to something else than the default value of 120fps. (as vvvv tries always to get the most out of your cpu, empty patches tended to completely hog the cpu while having astronomic frame rates. so vvvv defaults to 120fps). the frame rate within vvvv is controlled by a windows performancecounter, so it should be as precise as possible on a windows machine.
obviously the brain processes audio information with much higher temporal precision, while the eye is happy with everything running at 60fps, the ear is not. so you currently wont get high quality realtime “music” synthesis within vvvv. many issues are to be discussed to get this working, like how to deal with multiple frame rates within one project. one of the things which makes vvvv much easier to use than pd for example is that all data flows only between the frames. this avoids many nasty synchronisation issues which makes debugging pd patches quite complicated.
to do beat accurate stuff you probably want to do many calculations with 1 beat= 1 frame, while other things should be 1 frame=1 audio buffer or even 1 frame=1 sample.
having more suitable audio frame rates is desirable but we like to see this as a special case of a more generic problem - having multiple graph evaluations going on at the same time - like having the interface in another thread as the rendering, integrate it into boygrouping, having flexible mechanisms to resample between different frame rates, sync incoming video streams with fixed frame rates to clusters of machines with different video output frame rates, etc. so dont expect anything in the next beta.