The satellites are not in stationary orbits. Since they move, the receiver interprets that as motion and displays it as speed based on the number of satellites being tracked.
The number of satellites that are providing position data is low, so that gives you the high EPE number and the high HDOP number. More satellites= higher accuracy.
This is what I get with a couple of my Humminbird Side Imaging units:
In both cases I was moving on the water.