9740 kb/s would be 9.74 Mb/s.
Factors why the Hopper isn't as fast could be the network interface drivers, overall internet traffic, "slow" or overloaded servers at Dish's end, and so on.
In the end, you're probably worrying about nothing. Look at what Netflix says for streaming here:
https://help.netflix.com/en/node/306
Those speeds are what your internet provider lists. You appear to have 150Mbs service, 6x faster than Netflix recommends for Ultra HD. Even the worst case you describe is far faster than 25Mbs service they suggest.