I've had my share of squeaks and rattles with my 2013 ATS Performance 2T, the ongoing one is a rattle in the steering column that can never be replicated. The intermittent ones are so hard to troubleshoot.jlukavsky said:
Your best bet is to find a stretch of road that's near the dealership where the sounds always happen, go to the dealership and ask your service advisor and a technician to ride in the car with you as you drive that stretch. When they hear it with you, then they can troubleshoot and make the fixes.