I sent the tech line a msg on the bad reviews on the variable tone new dynomaxes
where the flapper valve inside the muffler was noisy....this is their response.........
Thank you for your inquiry for Dynomax Exhaust. We appreciate your interest in our products. The valve in the VT muffler had a clearance change in late 2010. As long as a balance tube is used in a dual muffler system there will not be any valve rattle at idle.
If you have any further questions, please feel free to contact our tech line at the number below.
Thank You, Adam Stacy Adam Stacy Dynomax Performance Exhaust Installation Technician