Hoping someone has an idea here! I took the Vision to do some spectacular photography today, but when I went to engage the rotors, only the two white blades began spinning and responded to thgrottle. The black blades simply sat and pulsated. Power down, restart, same problem. Of note, I had prop gaurds on earlier in the day and had taken them off, so thought maybe I had over-tightened the screws after having removed them. No difference after adjustement. I went about my morning and tried again 30 minutes later, this time, three rotors pulsated with only one remaining responsive to control. I replaced the prop-gaurds on returning home, but no change. Now all four blades are doing the pulsating thing with no resonse to throttle. - tried a second battery - all connections reportedly good - no issues with camera/wireless connection Of note - there was a crash yesterday into a tree, but the vision flew immediately after and even for another backup battery (mybe 45 minutes flight time post-crash). Any ideas? I'm on vacation and don't have access to a computer yet for diagnostics.