Image shrinks then becomes normal size due to cables not tight.
Cause:
The cables and cords that attach the monitor to the base unit and into the electrical outlet are not secure and tight.
Solution:
Tighten and secure all cables.
1) Secure the display unit power cord into the back of the display unit and in the electrical outlet.
2) Secure and tighten the monitor cable to the back of the computer.
NOTE: Make sure that the finger screws are completely tightened.