There should never be a loud rattling noise on any car when the clutch is pushed in. It is normal to hear a whine if you are in 1st and going more than like 10mph because the wheels are spinning the transmission and 1st gear is very low - so it is spinning very fast.
The dealership works for me, not the other way around. I don't care what they say, I will make sure that my issue is recorded in to their system exactly as I describe it. Anything less than that will require the service manager or a call to 1-800-Hyundai before I will take it off their lot.
That said, my dealer has already called me as part of a quality program and asked me if anything was not 100% to my satisfaction and told me to bring it back in if I have any problems at all during the next year and they will give me a loaner and another free oil change.