First GoPro flight! (non-FPV)
I strapped the gopro to the tray and made sure it would hover. Then I took it outside for a quick look-see. Works great!
Note: The scratchy sound ended up being my velcro battery strap rubbing on the case mount (or on itself). That said, I think there are still vibes that need to be ironed out. The recording quick test flights with the gopro might end up being a good way to monitor the effect of different vibe elimination changes.