Gday. Welcome to the forum waikeungyk.
ATM trying the Z60 Master, i too have gotten this at times, that be while installing it, after it have gone in and the wires in place i have not heard this.
Also before i got it in the car i ran it in the living room window testing memory cards, dident take much meddling with it to cough up a issue with a remote camera.
The wire harness is a bit different as i am used to connecting remote cameras directly to the front main system, guess they also do on the Z60master but with a twist.
But ever since dual systems came about and so with a remote rear camera, issues in this regard have gone up of course, and very often due to either broken wires or plugs coming loose.
Plug in rear cameras can for instance happen if you have too much wire there and so it can wiggle loose over time or by slamming rear hatch in my case, so important to use a couple of cable holders in that area.
I do have some slack on the rear wires in the front, but as i said have not had this on sort of OK Danish roads, maybe if you hit more bumpy Aussie rural roads a disconnect would happen faster.
Any plug to plug connections, after properly connecting the two, you could secure them by wrapping a little tape around the plugs so it would take more for them to wiggle apart.
My car have precious little room above the headliner in the front, so had a hard time cramming everything in there as there was already wires from other system.
