Since you are not getting a solid power light on the Slingbox, the might be caused by an AC adapter failure.
We recommend you to check the following link to retrieve some troubleshooting steps and, if the issue persists, contact the Technical Support Department, so we can arrange a replacement.
I had the same problem, as do so many people dealing with this issue – which generally can be attributed to an inherently defective power supply. On eBay, I suggest that you go to a store called “TopPowerAC” and purchase the power supply unit that they sell for your model slingbox. (I have a Pro-HD.) It should cost you around $10. I plugged in their unit and my issues were resolved immediately! It might be worthwhile for you to try this as well.
(As a public service, I am posting my reply in multiple discussions because of the prevalence of this problem.)