I believe on the product page to which you refer, they are talking about using IR commands to control amp volume. Just before the reference to volume, IR is mentioned. Most or perhaps all A/V-remote-control accessories utilize (or can) IR LEDs to output learned or looked-up commands to other devices. So one would "teach" the volume IR commands for your amp to the interface or software (wherever the smarts for this feature are located), and then the JRiver remote (and possibly s/w inputs) could be used to trigger the interface to send the appropriate command.
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