Its definitely not a ticking sound. The sound is metallic and sounds as if a heat shield is rattling under the car under light acceleration. Its most noticeable when accelerating in first and second gear. It might be present in other gears as well although road noise tends to drown it out past second. I had the car inspected at the dealer when I took it in and neither me or the mechanic could find anything loose underneath the car that would make the noise.
