Audio problem: When Rembrandt is walking down his steps to his car while singing the national anthem, the words don't match what his lips are doing.
Other mistake: Quinn is watching the video of the basketball returning from the vortex. The video shows him catching the basketball, then we see a shot of Quinn pressing the fast-forward button until he shows the basketball to the camera and says "and the crowd goes crazy!" The problem is that even though he pressed only the fast-forward button, the video fast-forwards from a point before the basketball came out of the vortex, which is impossible since Quinn never rewound the tape.
Other mistake: Quinn's alarm clock turns on, then about 8 seconds later we see the time change from 7:59 to 8:00. All clock radios turn on when the time changes, or possibly fade in slowly a few minutes before the alarm time, not a few seconds before.
Revealing mistake: The doorway inside Quinn's house on ice-world is lined with snow-covered icicles. Watch as Arturo walks through this doorway; he bumps into the icicles and you can see that it is just a bunch of cotton.
Answer: The show's creator admitted that it was the wrong Arturo.