Theres so many sound deadening devices on these exhaust systems, that little bit of packing probably own't even make a noise difference. There are 2 turbos, 2 pre cats, 2 cats, a HUGE muffler, and a resonator. I wouldn't worry a bit about it. The mufflers usually are like 3 wraps and 3 layers thick. It probably rusted one layer away internally and blew out that packing. It'll probably take another 100K to rust out layer 2.......