They get quieter the more you put through them, it might quieten yet more after another 100 or so.
I love mine, and use it for all my shooting, i dont like wearing ear defenders and also dont want to go deaf .....that was the main reason i bought it.
Do you clean the mod?, i have to take mine off to get it in the cabinet and lots of crap comes out when i take it off but i dont wipe it down i just put a little oil on the threads.