About a year ago there was this rattling sound coming from underneath my car whenever I was in reverse. It then escalated to be WHENEVER i was in some range I can't remember (something like 2k - 3k rpms). I took it to a performance shop, and the guy immediately knew what it was when I told him what kind of exhaust it was. He then showed me a crack at the welding point on the resonator. So I got it welded, and the sound went away. Now, about a year later, the sound returns once in a while when I'm in reverse. Does anyone else have this problem with the GReddy SP system? I think I'm just going to weld it again if it gets worse. I don't have the money for a new exhaust.