Don't be wary, because there is only one real adjustment to make, which of course is the delay.
If it's only one channel, you know, that's not so bad in the grand scheme of things. Some shows, even some movies, have really bad sync. They should all be on the dot perfect to a standard, but some SMPTE engineers perform less admirably than others.
If the lip sync on CBS is completely unacceptable, and this idea IS a hassle/nuisance, but you could try a new set of connections only for this channel, with its own delay setting in the receiver. For example, component from STB directly to tv, and a SPDIF from STB to receiver.
While I'm at it, may I also recommend trying OTA for free. It will look better than any cable signal, and it's free. A decent antenna can be had for $30, then just connect it directly to TV's ATSC tuner with a video coax cable. Use this resource to find your signals with respective strengths:
http://www.tvfool.com/?option=com_wrapper&Itemid=29