Frozen Camera

Is it just me, or does the camera get perma-locked until I die sometimes? There's a pattern that occurs before each time this happens.

1. I move my cursor onto my minimap to have the camera move automatically without me clicking to where my cursor is on the minimap.
2. I press the spacebar in order to get the camera back on my champion.
3. The camera then locks onto my champion, and I can't unlock until I die.

Not sure if I explained it clear enough, but if you know what I'm talking about, feel free to help me make my post clearer in the comments. Thanks!