re-tightening of the valve cover seems to have done the trick. i recall having difficulty hearing and feeling the torque "click" upon initial tightening. could be a combo of cheap torque wrench and low torque specs.
Probably a good bet btg. I need a V.C.G. replacement on the VX. It leaks slightly at a bolt or two., but I haven't had to add any oil in 3k miles since my last change. I'm waiting until my valve adjustment to replace it, though. Going to fully synthetic 0w-30 next.