Read
http://www.remotecentral.com/features/irtips.htm
http://www.remotecentral.com/tsu3000/index8.htm notes more about a 2 second delay.
Beyond that, ask Pronto directly how to solve.
I’m programing a Pronto to work with an LG OLED65E6 TV using its Smart Remote which transmits both IR and RF. The Pronto refuses to learn IR codes from it for several of the buttons. For a few of these, I was able to use codes from the Remote Central database, but some essential ones such as Enter, Exit and Up/Down/Left/Right are not available there. The TV's User Manual has a list of 2--digit hex codes for the remote's buttons but I have no idea how to convert them to Pronto format. Any suggestions would be appreciated. Also, why does the Pronto refuse to learn certain buttons?

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