You can perform a KVM (AKA BMC) reset to solve a lot of the connection problems that are occuring during the KVM connection. You can reset the BMC in your clientarea. Please follow these steps to perform a KVM Reset. The reset takes a couple minutes to finish, so wait patiently as it's finishing.
Step 1) Log in your clientarea
And click on the (Dedicated) service of which you would like to reset the BMC.
Step 2) Reset your KVM
Navigate to the "KVM Management" tab and click on "Reset your KVM".
It can take a couple minutes before the service has been successfully reset. After which you can continue launching the console