When the boys play the pants like a bass guitar, stretching them would actually make the notes higher, whereas it's the opposite here.
When Popeye smashes the radio believing it to be the source of he music, one of the revealed tubes glows as if it's powered up. However, the radio is not plugged into the electrical outlet that is on the baseboard next to the table where the radio had been.
Popeye's lantern that is sitting on his steamer trunk casts a different shape shadow on the wall than the lantern actually looks like.