Ever since putting the dual OEM exhaust on my car it whistles like crazy when i stomp on it. It's not the turbo, cause it didn't do it the day before i put the new exhaust on. If i step on it normally or even just a bit aggressive, it's dead quiet. But if i punch it, once it kicks in it has a high pitched screaming whistle. Would a small exhaust leak or pinhole in the weld they did at my flex pipe make this whistling sound? Any help i appreciate it.