Sound and bang when shifting gears

[melyta]

Hi Experts,

I have a Toyota Yaris 2012 model, bought in Romania, Europe. It only has 51.000 km run, but lately whenever I do about 30km with it in some traffic it starts making a bang under the pedals and also it makes some sound (also coming from under the pedals) whenever I shift gear, especially at low speeds and low gears. Did anyone by any chance have a similar problem or could anyone give an opinion on what this might be? I really hope it's not the gearbox :(