Few concerns regarding a 2012 Chevrolet Impala 3.6L V6

Car has 105,000miles

Concern 1: Humming/droning noise coming from somewhere in the front end when driving over 25mph. As I speed up the humming increases in frequency. The noise continues even if I let go of the throttle. (this is the exact noise) https://www.reddit.com/r/MechanicAdvice/comments/1e3ruun/hummingdroning_sound_at_certain_speeds/

Thing is, I changed both front bearings and rotated the wheels and still the humming persists. So I'm really not sure what it could be.

Concern 2: Slight knocking noise coming from engine area when I accelerate from a standstill. I suspect it to be a CV axle, but I'd like a mechanics opinion. (noise in attached video)

Accelerating

Concern 3: Not sure if the engine bay sounds as it should. Maybe some other owners of this vehicle could chime in.

Does this idle sound normal?

Concern 1 is really what I'm mainly worried about (hopefully it's not a bad axle shaft).

And thanks for the advice.