It happens if all of its weapons fire on the single target that enters range for a little bit. Then anything else entering range won't be fired upon. As long as you can keep that first ship alive, that's the only thing that will be hit.

But, you can fix it by giving the starbase an attack order, it'll reset the weapons and they'll start shooting normally.

Thanks for the tip mate.

Rather than clogging the forum with everything I think of I just thought of another issue I should report.

In long games in the later game loads of special effects stop working.  I believe this is probably to do with saving the game and loading later although I haven't tested to be sure.  I seem to remember only noticing it happening when I load a save game.  Anyways the main effects that seem to dissapear are the light show when a ship levels up or explosions and I also believe certain attack types because sometimes it looks like ships are fighting a losing health without any bullets / waves / whatever being fired.

This isn't a new issue with Entrenchment, it's just something that I haven't thought to report before

I've had it where it was attacking a frigate/cruiser at first but all the weapons are firing all over the place and once the full fleet is in range and there is a cap included, it focuses on the cap with everything its got but just the cap...that is until I tell it to attack something, anything really, I believe even the same cap.