Go here and download Rotel "All Rotel 10 Series Models Master CCF File"[Link: bwgroup-support.com]
Google for CCFExtractor_4000B.zip
Extract, run CCFExtractor.exe, select the downloaded Rotel10Series.ccf
Look for RSX-1057, select a function on the top box, a corresponding hex codes should be displayed on the bottom.
Hope that help and good luck.