Garfield Headphone Softies are one of the best ket secrets of many mixers including me. They help keep your ears warm in the winter and cool in the summer. They are made of Rayon which has no effects on the audio. They are available at most sound retailers for under $20.00 try a pair out they are great below is what Garfield says about there softies:
Headphone Softie is a set of soft headphone earpad covers, made of a velour-like rayon chenille fabric. The colors available are black, blue, green, gold and red.
The covers will fit most full-sized, circum-aural headphones, such as the Sony MDR-7506.
This product is designed with both practicality and comfort in mind, providing a nice cushiony feel for extended wear.
It is also resistant to temperature extremes by providing warmth in cold weather, and deflecting perspiration in hot, humid locations.
The headphone softies have no adverse effect on the frequency response or audio delivery of the headphones.