Edge of Hearing

I strained to hear the faint words coming through the headset. 
But for the life of me, I couldn't comprehend what my coworker was saying.
The words were like the white noise generators, a distant humming, on the edge of hearing. I knew my coworker had said something. But he was so faint. I had no idea. 
"What was that?" I asked, cautiously turning up my volume a notch to see if it helped.
It didn't.
I tried again.
No change.
"Could you put the mic closer to your mouth? I can't hear you." I tried again.
To no avail.
Still very quiet.
Still on the edge of my hearing.
I couldn't comprehend it. Why? Why out of all of us at work, was he the only one I couldn't hear. It wasn't my end. It had to be his, yet he refused to alter anything, stubbornly stating that this was how it was always done.
But if it was how it was always done...why could I not hear him today?

-Inspiration from Work