Crunching/Crackling Sound

[Xonos]

I have a quad rotor setup with multistar motors (Multistar 2212 - 920KV Multi-Rotor). The layout is the deadcat/spider configuration.

My two front motors (the ones farthest apart) get much hotter than the rear motors and I am starting to hear a crackling sound coming from my quad which only happens when I'm flying. It doesn't happen while I am just spinning them up on the ground. I just wanted to know if bearings would be the issue and if anyone of you have had similar issues. Here's a video I recorded today and you can hear this crackling during the flight.

 

[Montiey]

unless your motors are jammed, I wouldn't worry about it. It might be a loose bering, which can be very bad, but it might just be something less important. Try to see if the motors are loose in any way, or click when they turn.

 

[Tench745]

I'm no expert, but that sounds a bit like an electrical short happening, I'd suggest checking all your motor leads carefully. Interesting that it only does it when flying. Can you replicate it if you hold it off the ground? How about with the props off? I don't know how you'd test a sound you only get in flight when the props were off.... but every little thing you learn is a step closer to an answer.