VPI Classic 1 and Dyna 20X2

I've had my Classic one for a couple weeks now, and the first cart I mounted was my Dynavector 20X2L. Initially I really love the sound, but gradually noticed that it was sounding rather aggressive in the treble. I experimented with damping fluid, VTA, VTF, loading, etc. The best combo I found was to have the Dyna loaded at 30 ohms, using damping fluid. I love just about everything else this cart does.

I then decided to mount my Grado Sonata1, and to my surprise, I haven't experienced any hum issues. It sounds much smoother in the treble, however, at times, I can still hear somewhat of a "ring" in the treble with certain things such as bells, cymbals, triangle, etc.

Could this be ringing from the aluminum platter on the Classic? Has anyone else noticed this?