Can you describe the sort of interference you are getting? Is the radio properly tuned to the required station?
I have two Nextbase 402G cameras installed, front and rear. They are both powered from the accessory sockets, the front one, from the socket under the dash and the cable is routed around the screen, under the trim. The rear is powered from the socket in the central cubby box and the cable runs under the rear carpets and through the boot, with the camera bolted to the rear parcel shelf.
Neither gives any interference at all.