Most control panel buttons do not work and cant click on anything on screen

Hi all, Looking for some assitance on an Esaote MyLab40. This issue is mostly there, but sometimes it works correctly. System boots, but you are unable to switch between the tabs ot the top of the sceen while it is starting. The QWERTY keyboard is unresponsive. CAPS lock remains on.  Some buttons on the control panel work. Trackball can be moved, but the three buttons around it do not work and therefore you cant select anything. Menus can be brought up by pressing the buttons like 'tools' and 'Menu' etc. The mouse pointer can move move.  The ON/standby button just below the monitor doesnt work. System freezes shortly after it has completely booted, then a message appears saying it wasnt shut down correctly and the system freezes. Because the mouse clicks or QWERTY keyboard buttons do not work, the message cannot be cleared and system is unusable.   Reseated all boards and cleared out a fair amount of dust from the PCB's. External mouse doesn't work on the system either, cursor doesn't move. Is this cable to control panel board, control panel, faulty QWERTY keyboard causing this issue or perhaps the PCB with all the VGA etc connectors on it? thanks.