When the car is in third gear, I can her gearbox noise. The car has done this from the start.

Should I be concerned, some have told me that the S4 is noisy.

Appears to be only in third and at slower speeds, lower RPMS.

Thanks

This is common in gears that are course in pitch @ low RPM.
The gear box can be pulled down and 3rd replaced ,but you may still have the noise with that ratio.
Do the gear ratios feel right for what you are doing in the dunes?
Is 3rd gear a usable gear that you can get on the gas, or is it to high therefore in the lower RPM range most of the time and making the noise constantly?

The ratios feel spot on. I can dune in second or third, just when the RPM's drop when I am in 3rd the noise pops up. The noise goes away when RPM's get higher, or the engine is to loud and I can not hear it. Tranny works great and I have not had any issues. Just the noise had me concerned that something was up. It does not bother me, just wanted to make sure something was not about to break.

headsets with a radio makes all the cars noises and rattles go away..

Excatly, The noise does not bother me, just wanted to make sure that soemthing is not about to break.


With the headsets on I do nto hear anything.

Problem solved...