This sounds like you have disabled "Free snap". This is the button left beside "Snap on grid" in the snap tool bar.
When free snap is disabled, the cursor sticks on the nearest snap point, regardless of it's distance to the mouse pointer position.
We recently recognized, that this can happen by accident, with an implemented feature. Namely the space bar not only activates the command line, it also toggles the free snap option.
See
http://forum.librecad.org/2-2-0-rc-space-bar-deactivates-free-snap-tp5715907.htmlMaybe pressing space bar twice to activate the command line is a good workaround for this. Sadly this feature is not optional, you can't switch it off by preferences.
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