Hey guys, I got Invidia Q300 recently installed on my 15' IS350 RWD. The fitment was good but after a few days of driving I noticed my exhaust tips weren't lined up properly. Upon inspection it turned out be that the hanger pins on the exhaust are too small and kept sliding out. The exhaust on each side was hanging on one hanger instead of both. It also changed the sound of the exhaust. So, I got extensions welded onto those pins and it sounded how it did on day one. But, now it sounds different again. The rumble is slightly gone that used to come at 4k rpm. It sounds flat and there's a slight metal ringing noise. Also my left side exhaust tip sits slightly lower than left, which I'm assuming is my exhaust bushing that's loose. I've got it checked by the shop that installed it, there are no leaks. Sorry for the long post, any help would be much appreciated. Thanks.