Catch With a Closed Fist

I have a co-worker who I talk to quite a bit because we've become friends over the last few years and I enjoy chatting with her. There's one small problem though. She speaks so quietly that half the time I don't know what she's saying and I find myself nodding in agreement to whatever it was that she just said. I'll ask her to repeat every now and then, but I don't want to be rude and ask after every sentence. She's a sensitive person and has her feelings hurt easily, so I usually try to catch the gist of the conversation as best I can. The fault is probably mine in not finding a tactful way to tell her I can't hear her. The truth is, I've had that kind of problem all my life - telling someone I didn't understand what they meant, or that I couldn't hear what they said. My high school baseball coach once told me to be sure to catch with a closed fist. I was the catcher. I nodded and had no clue what he meant. How could you catch when your hand was a fist. It would hurt. A lot. It wasn't until years later that I found out he meant to keep my throwing hand in a fist so my fingers wouldn't get broken by a foul ball. That was some good advice, wish I'd have asked what he was talking about then, not that it really mattered anyway since my fingers are still intact. I don't remember him having any words of wisdom about catching the ball first before applying a tag or else you'll end up with a bloody mouth. Now that would have helped, but of course maybe he did mention that and I just didn't understand or hear him. Anyway, I often feel awkward when someone is talking and I didn't catch what they said. It happens quite a bit to me, and since I deal with the public there have been more than a few times when a person is talking then stops for a response from me and I end up looking like an idiot who wasn't paying attention. Maybe I just need a hearing aid.