BT business hub 6

[#1]

and the powerline adapter is switched off when not being used.

so is the TV connected via the powerline ?

Is the TV an android based one ? I've seen strange behavior with android TV I  standby, constantly  waking up and renewing dhcp leases

[#2]

No. The powerline adapter is used to connect my sons desktop to the router. He goes some online gaming, and dosnt like to use wireless.

yes Tv is android based, its a Sony Bravia, on Android Oreo.

It stayed connected usually for a couple of days, and when I come to use the TV smart apps, i see Ethernet not connected. Router shows that port as not being connected, but on reviewing the leases, it still appears to have a valid lease, and uptime?!?

I will try a static IP if it misbehaves in a couple of days, see how that goes.

I could use wireless, but I have this inherent dislike of using wireless for 4K or even HD streaming.

Thanks for the input.

[#3]

It stayed connected usually for a couple of days

That tends to agree with your DHCP lease time of 5 days. A client will attempt to renew the lease at 50% of the initial lease time. Seems as though the TV is trying to renew the lease and failing.

Some other suggestions here https://community.sony.co.uk/t5/android-tv/kd65xf8796bu-keeps-saying-ethernet-disconnected/td-p/2619...

[#4]

How do you switch off ipv6 on the business hub 6.....It's worth a shot. Failing that static IP seems the next step

[#5]

Hub has been up for 4days, TV for 96hrs. Still connected to ethernet..... This is with the only change being a swap of a cat6 cable for a known good cattle cable. I will monitor when the lease expires and see what happens, but I am surprised as the same cables are used for the other 2 devices on ethernet, the sky q box and the power line adapter connected to a desktop pc. Also noted in the devices tab on the hub, the Sony TV has a blue D superimposed on it, all other devices don't. 

The cat 6 cables are these from Amazon. Surely the TV wouldn't have an issue with a cat 6 cable....

https://www.amazon.co.uk/gp/product/B00JAHMHQO/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&psc=1

[#6]

TV still connected and renewed it's lease ok. I am completely amazed that changing to a cat 5e cable solved this, however it could have been a faulty cat 6 cable. I will buy a new cable so I can give this one back ....

[#7]

Unfortunately the cat5 cable failed with ethernet not connected,just after I sent the Cat6 cable back...... At this point I decided to take the business hub out of the equation and put the hub1 back on. Amazingly things have been good for over a week now, with no disconnects of ethernet to the TV and it's using a cat6 cable. It's my view that this business hub is faulty, due to the refusal to update firmware and odd date on firmware, but quite why it only affected the TV ethernet connection and not the skyQ box is beyond me. It wasn't even specific to a port..... 

Question now is, do i go for another business hub 6 or not. Anyone else had issues with a smart TV connected via ethernet, specifically a Sony TV...

If not I've been looking at to link Archer v600, but our family needs are modest.....

Any opinions...