I'm trying to help someone who just purchased this mixer used. Here's my question:

Is it possible to change the background image when you are using PIP? The manual is not clear on this. So once you set your PIP image, they want to switch the background between the two other sources. Can this do that?

Also, can you use input 4 for the PIP source, then switch the background image using inputs 1-3?

Thanks so much!