Just use the tiniest bit of clear nail polish instead of blue loctite - it does the same job and it is invisible so you don't need to worry about Apple seeing it and asking questions.
Can you elaborate? Is this a proven method? Links? What does the nail polish do exactly (meaning, why would it prevent it from loosening)?
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The popping sound is the bottom plate rubbing against the rest of the computer.
Can you explain more too? Not sure what this means.
Sometimes, I'll hear the pop even when I'm not pressing down on it, meaning, all hands off, and my laptop is just sitting there, and it'll pop.