mines standard and quite loud, almost sounds like theres a performance exhaust on it, and i know there isnt because i had a standard one fitted when i got the car. I took it back to the garage where i had it fitted, and they checked it for leaks or cracks, and they said it was all fine. My friend had a ph2, and his was the same as mine, got a nice low grumble to it when your pottering about. Mine even has a little pop on over run around 3-4k... Nothing wrong just how they are i assume.