I have had some issues in multiplayer where every now and then during a mission my character will completely ignore my cursor directions for an extended period of time and start path finding in a random direction. This is a large issue as it can render the game unplayable and entirely compromise progress in a mission ( ruined a boss fight once against redstone monstrosity by walking into lava) Luckily it does fix itself sometimes so i have been able to make some progress. I have a video of this bug but am unable to attach it due to size limits.