For some time, there has been a buzz in the gear lever when the RPM gets above about 2500. It also vibrates while this is happening. It happens in all gears. If I push the lever to the side, it sometimes suppresses the buzz but not always.
Is this likely to be a gearbox internals problem?

It is the newer type of gear lever mechanism with the ball at the bottom of the lever rather than the transverse pin.
