When Carly throws her sandwich at the fire alarm, she misses and the sandwich lands on the ground. She then takes her banana out and throws it and makes it, and it also lands on the floor. But in a couple more shots, the banana is placed at a different location - closer to the sandwich - and the sandwich is as well placed at a different location.
One of the times Freddie came out of the closet, on the screen of his lap top, the section where the 'iCarly' plays it said ICARLY, instead of showing what was happening on the cap cam.