The remote was learning the marantz remote and harmony remote fine, the U.R. MX-810 works the receiver fine with IR, but the RF extender won't control the Marantz receiver. I spent almost an hour tuning the variable IR output on the extender, but no luck. It must be the translation from RF to IR in the extender that's not working correctly, right?

Again, Marantz CODES ARE ALL NEW for the new sr6003, sr7003, rc8003, etc. receivers!
So, probably the only way to solve the issue is having the hex codes for the receiver. If I call Marantz, could they email me the new hex codes? They should already have the hex codes, right?