Hey all have a horrible under-dash vibration in my 07 rwd that only happens under load/acceleration around 1800-2000rpm. I have pin pointed the issue. It's the passenger side floor heat/ac duct that comes through the bottom kick panel. I have taken as much as I can apart, and put some half inch padding in between the plastics and fire wall to dampen the noise. This worked for about and hour then once I got on it, it started again! Been chasing this for a few months and it's driving me insane!! Any one else ever have this or a similar area-issue?Thanks in advance!