Quick fix; apply Flicker removal to the photos.
Unsafe colors and thin horizontal lines in photos can cause them to animate. Also high res files often dont downsize well.
Photoshop work can fix many problems. Resize to 720×480 (CS) or 720 x 540 (earlier versions)…maybee a little larger if you are doing motion on the stills. Apply a small vertical blur to areas that have thin horizontal lines like buildings. Desaturate areas of hot reds to below 235.