2017 brz radio issue
 

So I just bought my brz today and driving home the radio has a short. My radio worked for maybe 3 mins than cracked and stopped working than it would work again for a min and do the same thing again with no radio. I know there is some kind of short. What’s the best way to figure it out

Also the head unit is stock and everything is stock from what I can tell. Bought it off a lot so I can’t ask pervious owner

Issue is fixed. Rear 4 inch speaker was bad causing all the issues