So I have seen this posted a few times and I actually experienced this just recently with a friend in his V10 powered Audi. From what I have seen this is actually a common issue. To the 5.2 V10 cars.
They all seem to have this same issue
I experienced this the other day with a friend. But I have read read about this happening before to a few other people. In the case the 6000 laydown the car I was in did this in 1st gear 2nd gear and 3rd gear. But only on hard acceleration off a stop.
So my question is how many other people does this happen to.
Most of the time from what I have seen If you accelerate hard off the line the car will get into the upper range past 5500 and then the car will start to feel like your backing off the accelerator pedal for several RPM and then the car will slowly start acceleration again. Other timeis it will feel like the car is chugging in that rev range.
Im going to do more logging this week but the thoughts i have read some think this might be the intake switching over as that will cause a block in air flow. I think this might be part of it but it looks like it might be bigger then that.
I would think if everyone tried this that it might be shown this is a constant thing with all the cars.