Originally Posted by nakelp86
Its just asking for crash.
I had the same noise on my AXN floater and it would come up randomly.
Changed the timing on ESC to high and the squeal disappeared.
I like to add that I did not have that problem before till just out of blue sky it started squealing. So I have a feeling that ESC reset itself somehow by itself or I did it unknowingly.
So give try.
On the other hand I rarely trust stock electronics especially for FPV.
Gunny, I'm no expert by any means but, I watched the vid a couple times thru....and seems like it stopped each time associated with a 'move'. Hearing that it only happens when RTH is engaged, I might think system electrical works (eg, voltage) has something to do with it. Rather than it being mechanical. As in, the recognition/bind process chirps are actually coming from the motor itself. I'm also kind've basing that on some similarly odd noises from mine when I knew the LiPo was fairly depleted.
You might can confirm at least that part of it by installing a very fresh battery & getting it a good distance away as quickly as possible, kick in the RTH & see if that introduces the squeal....disengage & see if it's gone. Would narrow down the possible causes, can't speak for the condition however. If it doesn't
do it on full vs not-full, seems that'd be even more indicative.
When you sleuth it out, let us know what you found. Interesting!