Machine is underdosing [delonghi la specialista]

Hi everybody,

I recently bought a delonghi la specialista second hand. The dosing button was broken and the previous owner had glued it in place.

I replaced the button with a new one but i cant get the machine to give me a good dose off coffe grounds.

When the dosing button is at its lowest setting the grinder grinds for approx 5 seconds and at its highest setting 15seconds. This is with the x2 button luminated. But this will only give me around 9-10 grams off grounds.

I cleaned the grinder, removed the complete top cover and cleaned the whole machine while i replaced the buttons.

Can somebody tell me if i can do something else?

Beans are bought new at the supermarket.

Machine is descaled and water filter installed.

I reset the machine with the menu buttons.

Note this is the older model so i cant activate a extra grind option in the menu (correct me if im wrong)