Humming buzzing noise 45 to 65 MPH

Hello,

Typically, tires can produce humming noise. It can also be due to a faulty wheel bearing.

Can you tell if the noise is coming from any particular side?

Since it is a new vehicle and under warranty, the best option would be to have the dealer do an in-depth diagnosis.
If you feel like the current dealer is not listening to your concerns, you can always take it to another Hyundai dealer (given you have multiple close by).
Also, you can call Hyundai customer support and ask them to help as they can make the dealer investigate further.

Let me know of any questions.
Thank you.