When I started DM 3+ years ago, I quickly noted the cracks around but it was generally limited to the sessions.
Since then, I often feel (few times a day) like energy bubbles that "need" to expand from within me and then I just allow them to consciously be released => immediate cracks (especially affecting screens, plastics, woods, structures, etc.).
You are just noticing cracks that's where your attention is drawn? Three years is a long time, but if you feel okay(and not mulling over cracks all day), I wouldn't worry about it too much.