This issue only applies to a subset of units with OS 5.5.2 preinstalled. It's no software and no hardware problem. It's a corrupted piece of data. The Rig "MB - Guy Ton V30 B3" is normally fine. Copies of that Rig in Rig Manager, on our download page and even embedded in OS 5.5.2 are ok. Only the preinstalled copy got corrupted.
a. Delete the Rig (deselect Autoload before) and then press Factory Content under 5.5.2 to reimport the Rig.
b. Upgrade to our current OS 6.0 which you should do anyhow. The upgrade will repair that Rig.