I understand that you are having some issues with your Slingbox PRO-HD, since it does not work after the power cycling process.
If the Slingbox is showing a blinking light, it is not capable to get the IP address provided by the router. In this case, I recommend you to check the following links.
If after applying these steps you do not get a positive response from your Slingbox, the issue might be related to a faulty power adapter. In this case, I recommend you to contact us.