Same problem as others !
My bill was supposed to be $40.00 per month , the rep. lied to me ! All of a sudden in the last two weeks my service has slowed to nearly 0 ! Shows that I have used up the good part ! I have not been on as much this period ! Can't get a streight answer from support . Need to be able to talk to someone that can speak good English . Need to know when my contract is up so I can get Hughesnet junk off my property ! I was ok with the service till now . I've been mislead !
It's possible that the cause of your data being used is the new Dish Network equipment. I'm not familiar with Dish Network, personally, but I can say that utilizing data is one of the reasons connecting a DirecTV receiver to HughesNet is usually advised against. DirecTV's receivers can use data for things other than just On Demand viewing, such as Guide updates, and movie and TV show descriptions, and possibly even downloading those occasionally available "instant watch" films that are normally downloaded through DirecTV's own satellite dish. I don't know if Dish's equipment does the same thing, but it might.
I would advise, at least for the time being, disconnecting the Dish equipment from the HughesNet service to see if anything changes. Of course, you'll only know if it does if you have data available and are not in FAP, but I suspect this may very well be where the data usage issue lies.