I've also caught myself saying "What? Huh?" etc a lot these days. I have booked an appointment with an Audiologist for Monday.
Every now and then, my wife would say "it's time to have your ears syringed, you don't hear me when I talk". To which I usually reply "there's nothing wrong with my ears, you're mumbling". So I asked a colleague to look in my ears, thinking it was a wax problem. My ear canals were clear, and he sent me off to the audiologist. I have a noticable drop off in the frequencies where speech occur. Probably the result of 30 odd years of working with power tools and some shooting without ear protection. And listening to loud music on my iPod.
And I've never even played in a band... ☹