Your TSL's are bias ply, right rrdstar? I know I've heard lots about the bias Swampers flat spotting.
What is really weird is that I have yet to experience any noticeable flat spotting with my SSR's, but yet Schlud has it with his SSR's, and Will (who runs 32x10.50 TSL/Radials) also encounters it. Strange...I'm starting to feel left out.