Rattling/clicking noise while driving over 45 mph

I drove without the radio today and noticed this sound coming from the front passenger side. Not entirely sure. It sounds like a mix between rattling and clicking.

I can hear it when I'm above 40-45 mph. The sound doesn't change if I'm driving on a bumpy or smooth road. It also doesn't change if I accelerate or brake. But it does get a little louder when I'm around 70-80 mph. Anytime below 40 mph or at a complete stop, the sound disappears.

See video here of the noise (click on the hyperlink)

EDIT: I located the source of the noise. It's actually coming from the middle cup holder towards the backseats. If I grip the cup holder, I can feel the vibration.