Ok. So, yes car was doing the 'throaty exhaust' and 'heavy rattle' only in heavy rain on freeway or higher speeds above 50-65 mph. Car went in for yet another transmission slip on the eve of the Audi warranty expiration for the 12 month period from previous tranny swap which I covered cost and yes they found particles in the oil and Audi technical issued re-build tranny #2 from Germany at their cost!!! It is here and in removing engine and tranny found that the cat-converter mesh was torn apart and right side engine mount 'toast' ...so that can explain the sounds and sensations coming in every so often.... only at 82,000 miles and third tranny going in; do I get a badge of some sort as I have reached seniority...no? a little early?