I'm not really sure the best place to post this, but the solution may be an IP or RS-232 so I thought I'd throw it out here.

I have a digital information system that provides video over IP to remote TV's. That video is fed from a central location (ie 1 tuner controls 20+ TV's). The idea was that we would keep news programming on the remote TV's .. changing the channel every hour (CNN, Fox, Weather, HLN etc). I was able to do this by using an RS-232-controlled Contemporary Research unit hanging off a computer. But, since Comcast switched over encrypted digital, I have access to very few channels on the CR box. I tried using a Global Cache IP-to-IR system (which works great for controlling the DVD player we have on the Digital Info System), but the Comcast DTA's just don't react well to it.

So .. I'm basically looking for suggestions. Is there a (better) way to automatically change channels on a Comcast set-top box?

Remember, the issue is because of Comcast's policy to encode digital channels. I am not stealing services from them, this is all licensed, but any solution needs to pull these channels in and allow me to change them without human interaction. At this point, even something similar to the old VCR+ units would make me happy if they worked with a Comcast DTA!

If there's a better forum to post this, please let me know.

Sounds like all you need is a very basic automation tool . I am not sure why a Global Cache does not work for you , start with some basic troubleshooting . Did you place IR in the right spot on cable box ? 
 There are definitely some other solutions available . www.bitwisecontrols.com/ is one of them . There is also a PC based automation tool www.eventghost.org/ , Finally i know that IR is the most common way of controlling devices , but in the commercial enviroment i would look into something more robust . Unfortunately i do not know of any rs232 controllable cable boxes , however you can get a Tivo ( with a cable card from comcast ), then setup a control via TCP/IP www.tivocommunity.com/tivo-vb/showthread.php

I'll have to take a closer look at the TiVO option. I wasn't aware that they had the ability to control it via IP. Of course, it would have to be the output that is controlled (ie, I can't simply tell the TIVO to record a show and expect the channel to change). As far as the GC, I have a good amount of experience with the units. There's something odd about how the Comcast DTA remote transmits that the GC just doesn't work correctly. GC was willing to take a look, if I sent them a Comcast remote and DTA .. but the DTA won't do anything unless you're on Comcast's system.

I appreciate the info. It goes give me some other avenues to explore.