@mike53 That drove me nuts too.  I have 2 Nest webcams and I had one M5 exactly 4 FEET from both of them yet one connected to the M5 in my Bedroom about 70 feet away and the other to the L/R about 30 feet away all were on ethernet backhaul.  If I disconnected and reconnected the cams they would connect to the M5 right next to them but would eventually drop off and go back to the "far away" ones.  They were the only "bandwidth sucking" devices I had.  TP-Link would probably have been better off not putting that feature in,  :D   It was suggested I turn OFF beam forming and/or fast roaming but noe of that made a difference.  Maybe that's why that feature was never put on the M9's !!! 

@mike53 

depending on the adapter in your TV the issue is likely Fast Roam.  Fast Roam is designed to help newer more mobile devices to quickly tranport to different nodes as you walk through the home.  However on older device/adapters or ones that don't typically move through the home this feature can sometime cause connection issues or for devices that may be on the cusp to switch between node.  Also just because a node may be closer doesn't mean it has the best signal.  Even though the main node is further away its signal could be cleaner and hense why the TV is connecting there.  2.4GHz is likely being chosen due to the range and how far away the service is.  Defiantly try disabling the fast roam first though.

@Carl 

Hmmm....interesting. I had fast roam turned off. I chatted with TP-Link support yesterday and I was told to turn it back on as that would fix the problem. Now I'm confused.

@mike53 

If you can provide me with the Chat ID.  Fast Roam as the name implies only affects devices that "Roam" around the network it has nothing to do with a device that stays in a static location.  Another possiblity is that it is a priority issue.  If the units have equal signal stregnth then the primary deco has priority and the TV would connect to it.  two things you can try.  Forget the network on your TV and try connecting again. You can aslo try relocating the remote deco to see if its signal is improved.  

By the way what type of backhaul are you using Ethernet or Wireless?

@Carl 

The chat id is 13320086

I am using Ethernet backhaul from the deco closest to the TV. I tried forgetting the network on the TV then tried to re-join. When I tried to re-join, it failed about 5 times in a row. So I power cycled the TV and it connected to the correct deco and at 5ghz. 

I don't think I mentioned that I did a firware update to the decos earlier that day. Not sure if that had anything to do with it.

@mike53 

I'm a bit confused.  Are you using Ethernet backhaul between the Decos or do you have the TV wired to the closest Deco via ethernet?

@Carl 

Sorry.....When I had the issues, I was using Ethernet backhaul between the decos and going wireless from the tv to the deco. When I was having the wireless issues, I decided to switch to Ethernet from the TV to the deco and kept the ethernet backhaul to the main deco. That's how I have it now. I was just curious as to why I was seeing the issue when the TV was wireless to the nearest deco (the tcv and deco are literally 1 foot apart).

Interesting turn of events.........

This evening while watching youtube TV (which was connected to deco via Ethernet), I kept experienceing buffering issues. So I did internet speed test from my iPhone (wifi) and was getting 200Mbps speeds (consistently). Finally I decided to switch the TV connection from Ethernet to Wireless. It connected back to wireless no problem at 5GHZ and never had a buffereing issue watching TV the rest of the night. 

Appears something went wrong on the Ethernet connection from TV to deco. So, now I am back to running TV on wifi to deco via 5GHZ (closest deco) as expected.

Are there any issues I should be aware of when TV is wired to deco(ethernet). This deco is also Ethernet backhaul to main deco.

Just confirmed that the issue I am seeing tonight is with the Ethernet connection from TV to deco. Switched from wifi to wired and the problem of buffering and poor quality came back. Swtiched back to wifi and no issues. 

So, now how do I determine if the issue is TV adapter or the deco ethernet port? I suppose it could be a bad cat 5e cable but I'm tired now and heading to bed.