It's difficult to explain in text, luckily I was recording this game and have uploaded the video to youtube.

What happened was, I was attempting to instanly stop my ship by right clicking a base, so that I could teleport to maneuver my way around a bunch of enemies.

Not really sure what else I had done, but this caused my ship to get stuck at 9 knots, changing engine speed made no difference. You can see this in the video.

It was a combination of different key pressed most likely, probably changing engine speed while spam clicking the base at the same time.

It happens right about that the 13:00 minute mark.

The other possible bug, which could just be proper game mechanics, is both my recon and airstrike capital ship abilities becoming locked when being used while I'm currently teleporting. The short period of time that your ship is not currently on the field of play.

This happens at around the 12:00 mark in the video.

https://www.youtube.com/watch?v=6uDZ6Z0q-Dc