Thanks for playing! We are glad you found it fun.
Our musician actually mentioned the speed of the bullets too. My immediate thought was power ups. I am not sure if you are aware, but if you can get enough of the Speed+ powerups, a.k.a. the fire rate + power ups, then it will look like a stream of cannon balls coming from the ship. You only have a short window(20 seconds from the first pickup) for this to occur, since the power ups applied to the ship decay over time.