Tizzzzzz noise at 5000rpm

[DanR100]

Went for a drive this evening and all fully warmed up and running fine and joining onto a fast road i hit about 5000rpm and this noise appeared sounded like exhaust was vibrating, no actual vibrations in the car. I had the sports back box put on last week and was fine then but i doubt this would cause the noise?? It had a 12k service 2 weeks ago. Any idea's what this could be?

[Zad]

Catalyst / exhaust heat shield?

[clive f]

probably the most recently disturbed part of the car, check the exhaust out.

[DanR100]

Ok cheers guys will prob get her de-catted in the next few days and get it all checked out.