The UEI code made especially for Roku tv's is 14398 in newer remotes. See this thread at jp1 forum:
[Link: hifi-remote.com]I'm MaskedMan in that thread. That's where we post newer commands found via brute force searches. Searching 00000 through 00255 EFC's. After 00255 they start repeat.
We have a thread for Stand-Alone Roku's like Ultra:
[Link: hifi-remote.com]