Appreciate it, the second dealership said they couldn't replicate it so it has to become constant before they'll do anything. Right now they are saying it's a "customer satisfaction" issue and the vehicle is fine. Pretty poor service by GM to say the least, but I've got another 30 months or 31,000 miles while it's under full warranty so there is that at least. I'm going to start compiling more footage and documenting it every time it does it, hopefully a pattern will emerge or I'll figure out some way to trigger it so I can get it fixed. The service departments I've dealt with definitely have a high burden of proof and beyond driving it, don't really want to put in much effort to figure it out.