Product Images not 'zooming' since yesterday?

Has anyone noticed that your product images are not ‘zoomable’ ??
I noticed yesterday, thinking I’d done something wrong and even re-photographing a few. Then I noticed that the vast majority (not all?) of my old catalogue images were also static whereas they used to magnify when rolled over with your cursor.
Are Amazon tinkering again I wonder and will we get messages about incorrect images?