A4 TDI 130 - booms at certain rpm

[imported_youngcomp]

Hi all,
I have just bough a 2nd hand A4 2002 130TDI SE, and am more than happy with the car. However I have noticed that around 2050 in any gear there is a booming sound from the exaust. So you either have to slow down or speed up ever so slighly.
any ideas??
PS mine is the 5 speed model /ubbthreads/images/graemlins/confused.gif

 

[imported_colA4]

I have a 2003 A4 1.9Tdi 130 Sport model. I haven't heard and discerning Boom at this engine speed.

Does this boom occur when a window is slighty open? If so open an opposing opposite window slighty and the boom/drumming will disappear.

 

[imported_youngcomp]

no windows open! definitly the exhaust system

 

[VPMD7A]

I get this resonance at 1500 and 2500 rpm. Still intrested in a solution also.