i'm in the same boat, this functionality ceased a couple of weeks ago, i'm assuming due to a firmware update on the DVR. i'm in the mid ohio region. called support, they reset the box and the issue still persists. they scheduled a technician to some out to look at it... not sure how that is going to help, but maybe that person will be more knowledgeable with settings or if it has been removed.
i agree, i swear i saw this specific setting within the past couple of month. i've been up and down the settings and it appears this and other setting options have been removed, stripping it down to very basic items only. very frustrating to deal with.