See if you can get a video. The fact that it lasts that long makes me think its not oil related. If you shut the car off and start it again will it do the same thing. How long after you shut off the car until it comes back. Also is it exactly a minute long. try to time it if you can. Also try starting the car and if it rattles turn off the car and start it again a few seconds later see if that has any effect.
The thicker oil isnt bad in the hotter months.