Not the dialogue, you silly people. Of course that's not a bug! The "It's always 10 O'Clock" speech progression should only happen once Guybrush have left the screen, and then come back.
In the CD version someone introduced a bug where you can have the whole progression non-stop, so Guybrush complains that "it's ALWAYS 10 O'Clock on this island" a few seconds after he's first read the time - making the whole thing idiotic.
What SHOULD happen is Guybrush says: "It's 10 O'Clock". If you look at it again, Guybrush still says "It's 10 O'Clock". If you leave the screen and come back and look at the clock, THEN Guybrush says "Hmm. It's still 10 O'Clock". And so on.
Irritating that the SE team didn't fix it.