That is the first step to take. Go and try the radio somewhere else out of your area to see if there is interference with your frequency near.
2- Some new batteries come with defects so try another fresh set.
3- Inspect all the servo wires and anttenna wire to make sure they are not torn and causing a short (ex. a wire might have been pinched with a chassis screw)
4- Buy a new set of crystals, sometimes they may have a glitch
5- Inspect your radio antenna and see if it is screwed in all the way. Make sure radio has no visible signs of cracks from a fall
6- You could buy a new receiver, sometimes fuel could have gotten spilled on it. (replace the recv. and if that doesn't work go on to replace a servos.
7- Or just get a new radio set