2006 Prius Whirring/purring noise at 38 mph

My 2006 Prius is making a weird whirring/purring noise any time I drive it over about 38 mph. It stays fairly constant above that 38 mph threshold and does not change when I turn the car one direction or the other (making me think it’s something other than a wheel bearing). It’s difficult to describe the noise exactly, but it’s kind of a staticky vibration type noise. I’ve looked through several forums but haven’t found anything that pinpoints it exactly. Any thoughts on what it could be? I’ve included a video in case someone can help identify the issue from that.

 

So you can hear the noise at the beginning of the video, then I slow down to below 40 mph and the noise stops, then I speed up again to show where it picks back up again (around 38 mph). Not sure if that helps. The volume might be coming through more on my phone than others?

 

It might be trickier to hear on the video, but it sounds like kind of a rapid clicking that is coming from the drivers side. It’s difficult to tell if it’s coming from within the engine/electrical components or from outside of the vehicle, however it doesn’t seem to get louder when I open the windows.

 

Nope, no change in neutral. I was thinking maybe a belt? But my knowledge of noises like this is rudimentary at best.

 

And there were no precipitating symptoms for this noise other than kind of a brief and occasional hiccuping motion that seems totally random and kind of a clicking noise sometimes when I break or after I put it into park. Not sure if that’s normal for a Prius or if it’s related to this noise at all, but I figure any further info might help. I only purchased the vehicle about 4 months ago so I’m kind of clueless when it comes to diagnosing these things.