The device using the IR receiver is irrelevant if you're using the flirc. The flirc is matching keyboard commands to buttons on the IR remote. You don't even need an IR on the receiving device itself. People will add a profile in harmony that gives them the most options in terms of buttons/commands that have no relation to the hardware being used. Again, the IR on the receiver is a non issue. It can actually complicate the issue using the harmony software and matching the hardware (if you don't know what you're doing) because the device your using is responding to commands via the IR, yet your sending different commands to the flirc. I own an MCE IR (before I bought the flirc). If it works out 'of the box' with harmony, it's because you chose a profile in harmony that matched it (sorta, as the NUC has one profile). The flirc gives you a lot more options and as a NUC owner, running plex and Kodi I found it was definitely needed. However if the usb IR works for you, then great. Again, has zero to do with the flirc but simple operator error.