Those aren't earmuffs those are just regular headphones for music. Your muffs aren't losing volume your just losing your hearing from shooting with them....




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Just kidding!
I would look at the volume knob first like
@Talyn mentioned. If you're muffs are bad you can always pickup a pair of Walkers for short money like these here that even have Bluetooth capability for music of phone calls.
The Razor X-TRM series ear protection features gel-filled earpads and a premium cool mesh headband for the ultimate in cooling and comfort during those...
www.midwayusa.com