MCS image frame occasionally shifts in x axis

While a series of 50 frames were taken in the MCS engineering run, pin-hole mask spot on MCS image occasionally looked to shift by ~50 pixels in X-axis and went back to the previous position .
Example: visit 6878
https://sumire.pbworks.com/w/file/129778914/SpotShift_visit6768b.png
The image in problem has bad pixels at the left-bottom corner (see the following link), which may make read-out incorrectly.
https://sumire.pbworks.com/w/file/129778911/SpotShift_visit6768.png