ColorMunki not detected

[Federico Bruni <fedelogy gmail com>]

Hi,

on gcm the calibrate button is "off" and if I hover on it the tooltip
says something like "can't detect any calibration device".

The device is a ColorMunki Display.
As it is supported since version 1.3.4 of Argyll, I had to pin the
1.3.5 package in Debian unstable (on Debian testing the current
package is 1.1.1).

DispcalGUI can detect the ColorMunki, while gnome-color-manager can't.
What could be the reason?

Thanks,
Federico