I had a similar coming from the glove box area when ever I hit a rough patch of road. After trying to figure out where it was coming from for a couple of days, I finally found the source. It was actually the screws that run across the top of the glove box compartment. They are visible once you open the glove box. Two of them were completely loose and about to fall out. They screw into metal clips, so it was a metal on metal rattle. Easy fix. Something worth while to check out.
I'm working on tracking down my rattles. I'm fairly certain I have the dreaded door rattles but I thought I'd check all these as well.
Those 4 screws on the top of my glove box were completely loose as well. I'll have to drive around to see if that removed one of my rattles.
2016 GMC Canyon SLT Cyber Grey, 2" RC level kit, LED's throughout, Iron Cross steps, Line-X, Stubby Jr, GMC All Weather floor mats, Bull Rings x9, DRL harness, OPT7 LED lows and fogs