Several months ago, I installed these roof rack crossbars on my 2019 Soul.
They made a lot of wind noise starting at 40-45MPH. The wind noise continued until at least 75MPH.
Yesterday, I discovered this website:
soundproofcentral.com
Option #6 at the end of the article is the least expensive. I chose to try it. I bought a 48 inch bungee cord from Home Depot and wrapped it around the front crossbar. The 48 inch bungee cord cost approximately three dollars.
I have tested it up to 70MPH, and the wind noise is gone!!!

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They made a lot of wind noise starting at 40-45MPH. The wind noise continued until at least 75MPH.
Yesterday, I discovered this website:

How To Stop Roof Rack Noise
Roof racks are definitely a useful addition to a car. But if you’ve ever been driving fast and noticed a whistling noise, you’ve probably wondered how to stop roof rack noise. Here are some suggestions:

Option #6 at the end of the article is the least expensive. I chose to try it. I bought a 48 inch bungee cord from Home Depot and wrapped it around the front crossbar. The 48 inch bungee cord cost approximately three dollars.
I have tested it up to 70MPH, and the wind noise is gone!!!