Takeda Pipes and Exhaust Sound

[flyrchris]

Hello all. New to the Nissan Z. Bought my Z Performance in May. The stock muffler sounded kind of anemic so I removed it and replaced it with some Takeda pipes. It sounds much better. However, when the engine reaches about 4600 RPM, the exhaust system vibrates and it is annoying to the ears. Do anyone know of a way to fix this issue?

Thanks.