Canon EOS M Basic Instruction Manual page 418

Troubleshooting Guide
The subject looks distorted during movie shooting.
If you move the camera to the left or right quickly (high-speed panning)
or shoot a moving subject, the image may look distorted.
The image flickers or horizontal
stripes appear during movie shooting.
Flickering, horizontal stripes (noise), or irregular exposures can be
caused by fluorescent light, LED bu bs, or other light sources during
movie shooting. Also, changes in the exposure (brightness) or color
tone may also be recorded. With movie manual exposure, a slower
shutter speed may alleviate these phenomena.
Operation Problems
During touch screen operations,
the beeper suddenly sounds softer.
Check if your finger is covering the speaker (p.22).
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