I personally think the Satellites are overloaded now. I have the same problems in the evening. I figure once people are home from work and done with supper that they all settle in on their computers/tablets and it gets crowded. Used to have no problem years ago when I first joined Exede. (going on 5 years)
A few things could be behind it. Congestion such as Debbi is saying is one possibility. We have a few beams that are quite busy during prime time and Late Night Free Zone hours, we are working behind the scenes to relieve some of these areas, it involves a lot of engineering maubo-jambo that I only understand every 8th or 12th word of. But basically they are working on relieving these areas. Of course summer 2016 we'll be launching a new satellite which will effectively double our bandwidth. Now of course with that said, there could be some other factors (equipment for example) that could cause this too. It's one of those things where we won't know until we look closer at your account.