I have had the same issue with T2-C and RP6. Bad codes from a "learned" remote can and will lock things up. All emmitters will be in an ON state, and no other functions will work. You can power down the RP6 and it will reset, or wait, it seemed to take about 3 - 5 minutes for the RP6 to release the signal.
One thing to check, when learning the codes, make sure you press and hold the button you are learning till the program beeps or whatever it does to say it got the code. Anyone that was used to learning codes into Pronto's and other remotes will get caught on this one. Many of us are used to just pressing and releasing, and getting the beep, and you will with RTI too, but it hasn't checked the codes completely and you may not have the best "clean" learn.
I would also check other buttons that you have learned from the offending remote. It may not be all the codes just a few. In which case they may still need to be re learned. If still an issue, you may have to dig around and see if you can find a file on a site like this one for that piece is equipment. Or figure out another way to deal without those codes. If they are power, the RP6 has a relay that could trigger a power device, or plug it into a switched outlet at the back of the AV receiver.
Then there is the possibility that the cost of all this time to TRY to fix this problem, would be better spent just selling a device that you know works. It's a cheapy piece of equipment, if it was $1000's of dollars it would be worth the effort.
