So it looks as though I'm having similar problems with my slingbox solo, pro hd works fine, solo won't keep the network connection light up for longer then 5 seconds. I've tried everything from the help section, directly connected to my pc & swapped out cables, neither worked, all hard wired connnections, no slinglink or anything like that. The only thing I do get when I hook it directly to my pc is my network connection goes from identifying to disconnected every 5 seconds. So it seems as though the solo has an issue with it's network settings, which it can't get beyond.
I've tried resetting, I did do a firmware update to one of my sling's about a month ago, can't remember which though, I think it was the pro.
Anybody got any other ideas? Is it time to break it open and replace some hardware??