2016 Chevy Silverado 1500 crew cab. It has an up and down whistling sound and a clicking about every 1-2 seconds best heard at 0:38. What could be the cause?

 

I don't know if you have pin pointed the area the whistling noise or clicking sound is coming from, but I use about a three foot long piece of PVC pipe, at least 3/4 of an inch or larger diameter. I put one end to my ear and pass the other over the engine, till I can pin point the noise. Do not pass the pipe near the fan blades or belt, be careful using it.