What you would use ideally:
60hz refresh
gl_swapinterval 1
cl_maxfps 120, 90, or 66 (66 is ideal for double jumps, can switch to 120 for ramps, 90 for strafes and cjs, 27 for ladders and triples, 22 for standing djs/cjs)
cl_async 0 (i think client forces this anyways)
I had an issue a bit ago with awful response times at random points like you are having, I could have sworn it came up when I was playing the the cl_draw cmds, but who knows. I did a fresh install and I never had the issue again.