A few quick questions: Does the noise increase with RPM's, is it consistent, does it only occur at a certain speed/gear/rpm, is it only when driving/idle, did it occur before the bypass install, is the rattle metal to metal...plastic to metal etc.

I've had both the SRI and the CAI. My CAI hummed, and my SRI whistled. Neither of the noises were consistent, or "normal". IMO the SRI was the better of two evils. With the CAI I lined all of the reasonably close metal edges and corners with flex loom; this helped dampen the hum...but not eliminate. With the SRI I swapped to a K&N filter and siliconed all the joints. The whistle was gone but the intake was louder and more flashy than I prefer.

Unfortunately after a recent (unjust) run in with the LA POlice department, the factory setup is back on (Damn state ref). On the bright side....I’m moving from CA in 6 months, going turbo, and leaving the SRI/CAI saga...

Good luck!