Precision 7540 + Dockingstation WD19DC - still not working

Hi there,

we have several 7540 Laptops which are having issues with dockingstations.

Dell Command Update 3.1 says als Drivers and Firmware are installed but the user experiences regularly this issues:

- Monitor is working but the mouse (usb) is not working 

- Monitor and Maus are working but netzwork isnt.

- Laptop crashes with als monitors black (even the one from the laptop)

- only one LED of the connector from dock top laptop is glowing -> laptop tells decreased functionality

Any hint what will stop this once and for all?