The damage to Mario and Luigi's rock TV changes after it's broken.
In Rock TV, during the scene where Mario and Luigi are wrestling, you can see when they hit the ground Mario is wearing Luigi's clothes and vice-versa.
As the orange Tyrannosaurus twin chucks Big Mouth Koopa, he is tossed feet-first. In the next shot of him in mid-air, he is head-first.
When Mario and Luigi were having a flashback of a phone bill, the amount says $1.295.31. It has a decimal in the place where a comma is supposed to be ($1,295.31).
During the wrestling match on the large TV, when Mario and Luigi collide with each other, their colors gets swapped (Mario with blue shirt, green pants and hat while Luigi has a blue shirt, red pants and hat).