Which units can you unplug the Gemstar module, & have the T.V's work
without it? The units with one, or two ribbons? RCA isn't likely to
have a fix for it anytime soon. Look at this link from 2001.

http://www.iwaynet.net/~nesda/SilentCTC.html

We have units come in, & work fine. Can you "tweak" the EEPROM?
Remember the old MTC
MTV-2047RF I think T.V.'s, you had to glue a bit of copper, or metal
over the micro, & put grounds on it! Worked great. Has the capacitor
mod worked for anyone? Place a 1uf 50V
capacitor to ground on U13101(15). This swamps the closed caption data
to the micro and stops the reception of the defective data packet.

The units I get, work fine after being unplugged, & brought to the
shop.