I have a skyline32 FC that seems to have weird issue: motors are seriously desyncing when I use transmitter. Swapping ECS/Motors around does not seem to have an effect: it's always channel 2 & 3.

Everything is calibrated, ESCs reflashed couple of times (BLHeli now). Input from TX is correct (used two different TX and RX). If I move motor slider in openflight, motor reacts as intended. But not with TX.

I have that on 1.12 cleanflight, interestingly enough, betaflight is actually almost fine.
Is it something specific to Skyline32 (read: it's dodgy), or am I missing something?

I'm running a skyline32 v1.1 acro I had this problem when I first got it. But a quick escorts and accelerometer calibration all was good

Try a different version of betaflight first.

But out of 3 i ordered, I had one that did this no matter what firmware I put on it. I ended up ditching that one. I think it's just hardware related to bad quality control

   
I have this FC too. Try installing BetaFlight  RC1.13 and re-flash your ESCs through the flight controller (it didn't work on skyline32 until RC1.13). I was having ESC issues (meltdown) and since I installed RC1.13, no problems. The ESCs were getting so hot that the solder melted and the parts moved...and then smoke and fire.