Amundsen fault

Hi a while ago my girlfriends Amundsen head unit started playing up or more specific satnav side of things. We can be driving and when come up to a T junction will just say "at the second" giving up no verbal clues so have to look down at the unit to see what it's on about. We've dropped it at skoda on two separate occasions for a update all under warranty but was also told they would replace the aireal and see if changed anything but now changed and aren't. But was told this unit has many known faults anyone else had any expirences with this unit or managed to rectify the issue