When you were in Canada, where you always watching the video stream inside the same house (i.e., the same local area network) where the SB is located? Or did you also have good access to your SB in Canada when you were watching from other locations in Canada (such as a McDonalds, Starbucks, or local library). What you are describing sounds to me like your ISP in Canada is not providing high enough UPLOAD speeds for the signal to stream smoothly from the SB to the router in Canada and through the modem in Canada out into Internet Land.
I doubt that your location in Phoenix is the issue, unless your ISP in Phoenix has some particular blocks installed on large data transmission rates over extended periods of time.
I have been using my slingbox here in Asia for a month and suddenly march 5th it cannot connect.
Nothing has changed on this side or in Canada.
Can't figure it out.
BTW has anyone recently had issues with having your login email address change when you try and watch.
I have found that unless I clean the cookies from my browser I have this issue.
All started suddenly about March 1 , 2012 maybe this is something to do with Dish Online?