You got a lemon car.At low rpm, the noise at mecomes from number support...I found the guilty one for vzzzz-bzzzz-gzzz, and killed it with some sticky glue. Now is silence...
I drove the manual 6 gear one here...the shi(f)ting is smooth...very short 1-2-3 changing, but is for consumption reduction...
The change-gear pedal is indeed a little tough to press it, but not very...is acceptable.
As for the buzz you hear in dash board at that rpm...is a mystery...feed the damn squirrels

))))) but seriously, check inside engine compartment if is all ok...maybe is some hole that catch air...or the indicator for rpm is mechanical and the cable is collapsing...