For troubles connecting to the Slingbox remotely, I recommend to have a look at these articles since it will be necessary to confirm if the issue is at home or just at that remote location. What's the upload speed at home?
Hope this helps,
Mark9716, what's the download/upload speed at home?, you can use this 3rd party link to test it: http://speedtest.net
I recommend you to confirm that the Slingbox is not overheating so it cannot be on top of a hot surface like a Set-top box or a video game console, this could cause this behavior.