many jura models have a pre-ground chute and it is a useful way of being able to provide decaf coffee.
Never put anything like instant coffee, drinking chocolate etc. in the chute, only
the correct amount of pre-ground coffee, avoid finely ground coffee as it will clog the chute (use ground coffee that is suitable for a Cafetiere).
The only other item allowed in is a coffee cleaning tablet (not a de-scaling tablet) when doing a coffee clean.
When putting Pre-ground coffee down the chute remember that the chute tapers down to a small opening at the bottom, if you simply turn the scoop upside down and the coffee goes down the chute as a ball of coffee it can get stuck and fall out onto the back of the drip tray. The machine will give you a message like' Not enough Ground Coffee'. The cure is to pour the coffe in over the edge of the scoop so that it flows smoothly down the chute.