Just had the same problem with my LucidSound LS45 … the headband is metal, I saw the recommendation to get them in one of those “buy it for life” threads so I did …

Turns out that the end caps of the headband are plastic and prone to breaking … I was able to save them by buying a non working “parts only” set on eBay and replacing the parts

This thing has been with me for 8 years and counting … they’ve been along for 3 motherboards, 2 cars and 6 girlfriends LOL