YEP! Proximity to metallic or carbon rods can make drastic differences to your receiver antenna. Metalized coverings can also prove disastrous.
btw, the problem exists whether you are using a megahertz or gigahertz range system, only the relevant distances are changed. It's even possible that one or both of your control rods is (accidentally) harmonic to your antenna's frequency, and creating a ghost echo in the incoming wave.
Welcome to the world of radio frequency interference. []