Thanks for the ideas.
Outlaw says 4 ohms is no problem, they accounted for the 2-ohm possibility.
I doubt I'm nearing 165Watts on these things, so I'm not clipping. There's no distortion that I can hear. It's still clear as can be.
It's just that details start to fade a little. The music still sounds GREAT, but the relative levels of everything shifts some.