Beginning Wednesday, July 18, I too have had the same experience on my old SD (4:3 480i)analog TV. I use the SD Video Out and Audio Out connections from the cable box but found that the coax ouput operates identically.
Like others, the aspect ratio for the SD output from the box is now reversed from that indicated by the menu description; i.e. selecting an SD (4:3) output from the menu produces an HD (16:9) ouput to the TV which makes the picture appear to be a zoomed in view of the upper left quadrant of the picture from the selected channel. To get the desired 'normal' SD picture an HD (16:9) ouput needs to be selected from the settings menu.
Additionally, after 'Confirm'ing the change, it now seems to take about 10 seconds for the change to actually take place. Even worse is that the ouput to the TV may or may not actually change, but changing channels will force the ouput to theTV to change.
The display of the menu items correctly matches the aspect ratio indicated in the menu selection. Thus one now gets HD menu displays with the desired SD channel display (or SD menu displays with the zoomed in HD channel display).
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