Closed Caption video commands

I am in need of a few frames of NTSC video in the form of an AVI file that I can edit into the start of my video productions for the purpose of turning off "closed captioning". I build computer based video inserters for restaurants. In a typical restaurant installation my customer will have multiple televisions in their facility connected to a satellite dish network for the purpose of watching broadcast television programming. My computer cuts into their system every 4 minutes and plays a 30 second video then turns the system back over to network broadcast. Here is my problem... Due to the high noise level in the restaurant, the televisions have "closed captioning" enabled all of the time. When my computer takes over and interrupts the broadcast network video feed, the closed captioning words on the television screen freeze and remain on the screen for 6 seconds. My video is covered up by these frozen words until they clear theirselves in 6 seconds, then everything is OK for the duration of the 30 second commercial. This problem is caused by my computer interrupting the closed captioning feed. The decoder on the television is waiting for the next words or a "STOP" command which it never recieves. Then it times out in 6 seconds and clears itself. What I need is a very short (just a few seconds) video file encoded with the necessary "code" to turn off the closed captioning function of the television decoder. I need this in and AVI file in the NTSC format. My goal is to edit this video file into the front of each of my video commercials. With these encoded frames played at the start of each of my commercials, the "closed captioning" should immediately turn itself off and provide a clear screen for my video to play. Can this be done???? Thanks, Mike