Issues with remotes and 4th Gen Apple TV

I have three 4th Generation Apple TVs. Two of them are within the same room as the TVs to which they are connected, while the third is in a cabinet within a different room from the TV to which it is connected. I have updated all of the Apple TVs to the latest version of TV OS.

The first two Apple TVs are working fine, whether I use the provided Siri remotes or if I use a third-party IR remote (an old Logitech Harmony on one and a URC MX-980 on the other); however I have not been able to get the third one (the "out of sight") working reliably with either the included Siri remote (bluetooth) or a third-party RF-to-IR remote (a URC MX-980 that converts an RF signal to IR using a "flasher" on the front of the Apple TV). FYI - the third-party remote was set-up using the "Learn Remote" function on the Apple TV. In terms of the unreliable performance, it ranges from very intermittent responsiveness (meaning sometimes a button/command is not received unless the remote is pressed multiple times), hanging-up (meaning the Apple TV gets stuck after a command is received - it seems to happen a lot in the various settings menus), or not responding at all.

One other bit of information, I originally thought it was a problem with the Apple TV itself, so I exchanged it for a new one, but the exact same problems are happening with the new one as well.

Has anyone experienced similar issues? If so, any ideas about resolving?