I'm working on an AUv3 AudioUnit effect extension and I understand the idea invoking a parametertree and observers to pass processing parameters to the render block. This is all working fine but now I'm facing the following problem: How to return processing data from the internalRenderLoop back to the ViewController?For example think about the gain reduction data that is easy to calculate in the render loop and that should be passed to the ViewController to be visualised for the user?So far I've tried three ways without success:1) Using the parameter tree - the parameter tree seams to be a one-way communication as I couldn't find a way to write to the parametertree from the render loop. The observers also seems to produce much overhead when the data is changing fast!?2) Polling the data from the viewController - I could not get a NSTimer to fire in the extensions ViewController? Used a scheduledTimer with GCD main queue but not get the timer to fire?3) Adding a write back to the render cycle - could not write back data to ViewController without capturing self.So I'm pretty much stuck and could find any sample code or forum discussion that would give me a hint. Therefore I would be glad if some one could point me to a direction how to pass data from the render loop to the viewController!THANKS!