That's actually happening, and isn't an effect. They're using analogue recorders because that's good/cheap enough to blow up after one use. There's a bit of a delay to process and transmit the signal, so it cuts out during the last bit of processing before it even registers the hit.

Which does make piloting it a bit tricky, too. And if you've ever flown any type of drone, you probably noticed it's faster than your reaction time, which makes these skilled attacks even more impressive to me. But I guess they also have a lot of practice, by now!