1) Are you trying to set up a pro (red) or a pro-hd (black)? You write pro in the heading, but is in the pro-hd section of the forum.
2) In which country are you trying to set it up in?
3) What point in the setup does it time out?
The reason for these questions are as follows...
1) If you are in UK and setting up a pro (red box), then it will fail on tuning, due to a fault in its firmware.
2) If you are in UK and setting up a pro-hd (black box), then you need to install .420 firmware, so that it will work with UK TV system.
Need at least to know the answers to these questions first
edit. I see others reporting problems with sling setup servers. Maybe this is causing your problem.