OK, we ordered aspheric polycarb with AR for a ~+150-+2.00D patient and put it into a plastic frame that's not really zyl. (It's a Lux Vogue 5163...it's some kind of polymer. Translucent, no wires, probably cold insert.)

When the frame flexes (+/- faceform) we hear a "creeaaakk" or a "squeeaakk" which is probably the one material grinding against the other. It seems like the "acoustic properties" of these two materials just reinforce each other.

So...what would you do? We don't need no creaking.