Mystery: What IS It?

Overheard by me: Jeremy talking on his phone softly in the mall on Wednesday.

Jeremy: Yeah, it's the weirdest thing. The one side is fine, but the other end is miserable. Only hot air comes out.
[pause for phone call recipient to respond]
Jeremy: (laughing) Oh, sure. My wife's not pleased. Can you help me?
[pause for phone call recipient to respond]
Jeremy: Thursday should be fine. I'll be up and in really fast so hopefully you can get a closer look. I'd like you to really poke around in there, you know, feel around.

After this phone conversation ended, Jeremy looked over at me. I KNOW I had a horrified look on my face. It was, however, not even close to the expression on the face of the poor woman who had heard the one sided conversation while sitting next to us trying to eat her Chick'Filet meal.

What is Jeremy talking about?:
[a] His very personal bodily functions.
[b] His truck.
[c] Our small home network connection.
[d] Henry and his not so personal bodily functions.

I just so happen to know the answer. I will not reveal it though. That is why this post will remain a mystery.