The A-B-C buttons on your remote do not have any use at this time. Also, the close captioning instructions are not written anywhere in the user guide. I strongly suggest that AT&T include them on the website where customers can easily find them.
Since the OP isn't coming back, and to clarify this statement for future readers--
Not true that NONE of those buttons function; the yellow A (triangle) brings up Ubar (in the beginning, it just brought up YP, shortcut for channel 97).
At this time the other 2 buttons do nothing.
And it's CLOSED CAPTIONING
At this writing, go to Menu > Options > Audio/Language Options > Closed Captioning.
From there, you have choices for Digital and Standard.
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