Problem is your timeline does not match your Project Settings


You have a Green Dot and an S on all the clips in the timeline

Check the Format and the Raster Dimensions of the footage


Make sure it matches the AVID Project Settings

AVID Media Composer >Preferences

Change the Format of the Project to Match

One more place to check is the source settings of the 

Master Clip


Right click the Master Clip and choose Source Settings


Go to the FrameFlex tab and check the Raster Dimension of the clip and the Image Size if they don't match 

Choose to click the button that will

"Reset to raster size"

Shown here


Then click Apply or Apply to all if you have multiple clips 

selected

Right click on the sequence and choose




Refresh Sequence > All