Problem change alpha 156

Hello!!! I have a problem with the change of my Alfa Romeo 156 1.6, when I try to put 4th the march does not threw, but it does not scratch or make any noise. In fact, he has never made any noise and this happened to me suddenly. Also sometimes the speed comes normally without making noise of any kind.
It seems as if I had a stop and not let the lever lower, but in the official service they have told me that it is the box but they were not very safe.
Please, if someone has happened to someone, I would appreciate it very much to answer me.
all the best.

I do not know that box well but if it is with a varillage system, then any barilla can be crooked, the 5 enters you well or does not have?

I would say that they are the cables of the change of change the photo of drawing 2.
You will tell me.
Greetings Toni

Hello, if the gear lever enters the place of the fourth,
I ratify you if it enters the place of the fourth, the problem
can be in the synchronizer, and if the lever is not located
in the position of the fourth is that you have a problem in the movements
between the lever and the fork
greeting