Polycom IP7000 stuck at boot

Hello,

We have Polycom IP7000 is stuck at booting up and hanging up. It constantly shows the Polycom logo with red LED's. I tried to reset it with 1357 but  nothing happens.  The unit stays with the boot logo for hours and nothing is changing. 

Is there anything i can do?

The MAC-adress/SN Number is below:

 Serial No.                Issue
 64167F06887F Getting hang, Partially working sometime
 64167F06786E Stuck on logo screen
 64167F068726 Stuck on white screen
 64167F067B20 Getting hang, Partially working sometime
 64167F06A039 Stuck on white screen

Thank you for your help!