Well, I just received my repaired headphones from the Koss repair center. All I can say is WOW. My old 1970s pair was cutting out on the right channel and the ear cushions were junk. What Koss sent back were a brand new pair no questions asked. All for $9.00 and they shipped them back no charge...

Just sent my Pro 4AAs in to Koss about a week ago. I will report upon their return.