Sorry for slow response; I tried to replicate the issue and, actually, it looks like it's not about audio mixer at all. It's even stranger!
If I have a second screen connected to my mac and the flow editor is on a different screen to the main Unity editor, that's when it doesn't work! If I drag the editor to the same screen, then it does..
So, I can do my job fine, but it's still a strange bug!
no worries, done.
Let me know if you think there's a better way...
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