I've been struggling with this issue for the past several weeks on my 4820X Ultra 4K in the living room. Roughly half the time when I press a directional button on the enhanced voice remote (the one that responds to "Hey Roku" and does a terribad job of understanding commands), it will behave as if I pressed the given direction 3-4 times. I then have to press the opposite direction to get to where I want to go.
Interestingly, the 4K stick in my bedroom with the older voice remote (AAA powered, no automated response to voice commands) does not do this. I swapped remotes between the devices and the behavior continued on my 4820X in the living room. This is not a remote issue, and given the behavior I would wager it is probably a debounce issue in the software on the device itself.
In addition to swapping remotes between the devices, I've also swapped devices between rooms, tried moving the 4820x to a different area in my home theater rack, changed from wired to WiFi (why is wired network performance such garbage, btw?), switched from my 5GHz network to my 2.4GHz network, and tried restarting. Every time the behavior sticks with the 4820X. The behavior is worst for me in the YouTube app (what I use it for 90% of the time to keep background noise going while I'm working) but it also occurs for me in Plex and Amazon Prime Video as well.
Seems like no matter what I try, the 4820X is frustratingly broken. I bought it because I made the mistake of expecting a good experience given my previous Roku ownership, and so that I could disconnect my LG TV from my network so I stopped getting spammed with 10-20 advertising popups when I'd turn my TV on in the morning. The last thing I want when I relax is to have to fight my media device to select the content that I want to view.
