Found a solution:
1. Open Applications -> Utilities -> Audio MIDI Setup
2. Left side of the window, halfway down there is a selection box for "Properties For:" - select "Built-in Audio" here (should have the Apple logo next to it).
3. Under that you'll see a series of drop boxes under Audio Input. Find the one marked "Format:" and change it from "96000.0 Hz" to "48000.0Hz". Close Audio MIDI Setup and try something with Flash audio.
That did it for me 🙂