Beasty YouTube video thumps?

I just scoured every room of my house looking for an intruder. I'm home alone watching Beasty guides on YouTube. I couldn't figure out where the random bump/thumping sound was coming from in my house.

Now I'm embarrassed because I'm pretty sure it's my subwoofer recreating the sound of him bumping his elbows on his desk! Is anyone else watching him on a sound system with a sub that noticed this?