Martin Logan CLS panel distortion

Dear Audiophiles,
My original Martin Logan CLS speakers developed harsh distortion at higher spectrum of frequencies (mostly audible at high pitched soprano voices). Distortion disappears at low volumes of sound. Are my panels getting too old (they could be 10 years old, I am a third owner)? Is there a way to clean/tighten them (the panels, not owners ;-)? Your comments and suggestions will be appreciated. Thank you.
Any opinions on the Anthem Amp 2 200w/channel hybrid for the CLSII? These are available for about $1k (I'm looking for a higher power amp to try out the CLSII).

Tonnesen, definitely try another amp before giving up on the panels. I've been driving my IIZs hard for 11 years, 9 of those with an Aragon 4004 and have had no panel distortion issues, just a flattening/hardening of the sound when I push the amp too hard. Just this week I've been auditioning amps to upgrade the Aragon and discovered that the 150W VTL couldn't even begin to drive the CLSs-- major distortion in the upper mids at moderate listening levels. Too bad since the VTL otherwise sounded pretty wonderful.
Those speakers can really drop in impedance at certain frequencies. So, like others have said - check your amp. You may want to check with Martin Logan to see where those dips occur,(if you don't knwo already) and see if that's where your problem is.
Golden ears,
they can dip and jump to increadibly high impedance.

The best successfull way to deal with them is to bi-amp using OTL that realy cares less about high impedances and beefy SS on the bottom certainly with active crossover.

All tube stuff is also possible having beefy VTL on the bottom and some 25...30wpc OTL at the top.

I actually heard many of Martin Logans speakers and no setup I realy liked with them and than they have one of the most complexed impedance characteristics on earth.
Martn logan pannel are just like airfilters they remove airborn particals from the room ,you will be lucky to get 7 years out of the pannel before dust dirt and grease from cooking loads them up .Even if they are away from kitchens and fireplaces.I got so sick of failing pannels in my many martin logans glad I moved on .