Okay, I'm typing this after taking some Nyquil for a stuffy/runny nose, sinus congestion, and headaches. Yep, I have one of those awesome colds everyone's been talking about.

It's also 1:00 AM, so I'm already a bit tired to begin with.

This is a bizarre occurrence, but I've noticed that whenever I'm sort of tired, music seems to play faster, as if the tempo is sped up a bit. It's really odd! I'm listening to a song right now, and it seems like it's sped up so that instead of playing (for instance) 20 beats per minute, it's playing 24. But obviously, time is passing by normally.

Why does this happen?

Try it yourself... You might have to listen a bit to catch the increase in speed, but for me it's definitely there. I've been listening to I'll Be The One by Backstreet Boys, and So Cold by Breaking Benjamin (I noticed the speed increase in that one the most).