Ido-mode working at half

[Andrea Crotti]

I have a strange problem with ido-mode, in short it works for
"switch-to-buffer" but not for find files.
If then I do
- M-x ido-mode
disabling and reenabling it than it works...
That means that something is overriding it (it's just "find-file" in
fact).

Anything that does it should be here:
http://github.com/AndreaCrotti/Emacs-conf/blob/master/.emacs.d/init.el

In general how could I track down what packages are "taking the control"
on what functions?

Thanks