I'm working with AE CC and all of a sudden everytime I click on the screen to zoom in or out, it defaults into audio preview, so I lose background and images (see screenshot). I'm sure I've inadvertantly switched something on or off but I do not know what or how.
Any guidence on restoring normal view as the default would be welcome.
Impossible to tell from your screen shot, but if you use 12.5% zoom and a custom resolution setting, anything is possible... Could be hardware acceleration issues then.
Try resetting your workspace or pick another one.