Just to further update, the two Apple TV 4Ks I updated to tvOS 13.0 three days ago have remained stable. No interfaces bouncing, no half-duplex, and no FCS or CRC errors.   For me, the issues were present from tvOS 11 to 12.4.1. ... View more

Sadly I believe the ball is in Apple's court on this one.   I've seen this issue on 4 different vendors switches, but not all AppleTV 4Ks display the problem.   However, I updated to the new tvOS 13.0 this morning, and since then my 4K switch port has been stable. Fingers crossed this resolves the issue! ... View more

I swapped the Apple TV 4K units between TVs, leaving the power, HDMI and network cables in their original place, and the issue moved with the Apple TV 4K. So this tells me the issue is isolated to the Apple TV, and nothing to do with the cabling, network config or TV. Other threads suggested that the issue may be to do with HDMI "chatter", but with the problem moving to the new location on a previously OK TV (different model, HDMI specs and cable), tells me it is not related to HDMI. ... View more

I'm experiencing the same issues (port constantly bouncing and high CRCs when sleeping), however I am using a Catalyst 2960S switch. Interestingly, I bought two Apple TV 4K (32GB) units at the same time, both are running 11.3 and connected to the same switch with exactly the same switch port configuration. One experiences the issue and the other doesn't. I've tried swapping cables, switch ports etc. to no avail. Both are connected to the same iCould account and have the same sleep settings. The only discernible difference between the two is the TV on which they're connected: Sony Bravia (no issues) vs Samsung. I will try swapping the Apple TVs between TVs and see if the problem moves or persists. I also have another customer who's experiencing the same issues connecting on Ubiquiti EdgeSwitches, so I would be surprised if Meraki are able to resolve this issue. ... View more