I notice that all these engines make extra noise at startup, I hear it in mine, I hear it on other people's Tahoes, and even hear it on videos where people capture cold startup exhaust sound (been researching new exhaust and watching lots of videos), but that video you posted is making an extra tick I'm not familiar with. It's the slower tick sound in your video that is new to me, not the really fast rattle sound, which is the one I referred to and think is normal on all newer Tahoes, but that slower tick with a more random cadence sounds odd to me. I'm not a wrencher by any means, just adding my observation as an owner, so hopefully someone with more knowledge chimes in.
