It is the thread direction - according to Sheldon, they're 'prone to problems due to the right-threaded fixed cup, which tends to unscrew itself in use'. That's exactly what's happening. Loctite it will have to be.
@TheorySwine started
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It is the thread direction - according to Sheldon, they're 'prone to problems due to the right-threaded fixed cup, which tends to unscrew itself in use'. That's exactly what's happening. Loctite it will have to be.