Some delays are accompanying this project.
The second ESC is dead on arrival.
But I was smart enough to order third at the same time - different brand (T motor), and its on the way. Such tricks can’t fool old system engineer.
Furthermore - Arducopter on newly fresh Navio 2 with some older RPi3 (i had it lying around) is taking 30% CPU (after apt upgrade), while same SD image on previous drone takes 15% CPU.
I will dig more into it, if it is version-specific issue or hardware-related. One thing for sure - on old drone “sudo systemctl stop arducopter” was taking 25-30 seconds, while on new - 1 second.
All these things seem strange and I will update in next days on my findings, while waiting for T-motor ESC.