Apple TV 4K - Ethernet constantly connects/disconnects while in sleep mode

I have been running down an issue where my Apple TV 4K, when connected via ethernet, does NOT maintain a connection link UP status while in sleep mode; it cycles up and down several times per minute. If the ATV4K is awake and playing content, this behavior does not happen and all is well. Most people probably wouldn't know or care about this, but I do since it causes unnecessary network chatter and is generally disruptive network behavior. I also have a 4th Gen Apple TV that is on the same ethernet switch and does NOT exhibit this behavior while sleeping, so I'm quite confident that this is isolated to the ATV4K only. I called Apple Support to report the issue, but they had no knowledge of the behavior.

Can anyone else confirm this behavior with their Apple TV 4K? I'm wondering if I have a defective unit and if I need to request an RMA, or if this is a problem with the ethernet controller or driver. That's what I'm hoping someone else in the Apple Community can confirm/deny.

Data points from troubleshooting

- Ethernet connection constantly disconnects / reconnects in sleep mode ONLY

- When the link status cycles, the ethernet connection negotiates alternately from 100Mbps to 1Gbps (could be part of the problem and suggests software/driver issue to me)

- WiFi connection does NOT exhibit the same disconnect/reconnect behavior in sleep mode

- Apple TV 4th Gen does NOT exhibit this behavior on ethernet (connected to same switch/router)

- Problem persists after bypassing the installed ethernet cabling and switch and connect directly to the router (several different ports)

- iOS 11.1 update had no effect

- DHCP lease renewals are not the root cause, but a symptom of the link status going down/up

- Hard-coding IP address only eliminates DHCP leasing, not the problem itself

And before anyone suggests it, I am NOT willing to leave the ATV4K on all the time to prevent this, and I am not switching to WiFi when I have a perfectly good ethernet connection. I am interested in prompting Apple into either replacing a defective unit or resolving the underlying issue because this is undesirable behavior from a network engineering perspective.

Thanks,

Andy