Custom Filter for Custom Field

Hey All,

I'm attempting to create a custom filter that will only show the tasks of which the custom field/column value is a specific value (in this case A, B, C, D ).  Custom filtering in the task names themselves seems to work fine, however, when I attempt to filter for the letter value in the custom field, I'm getting no results.  I've tried changing the search parameters several times with no regard.  They are currently at "Custom Field Name", "Contains"  and  "A".  I've tried "Contains Exactly", as well.  I'm not sure what I'm doing wrong here, as it seems to work fine for Task Name.  Any help would be greatly appreciated.