AC68u 5ghz band weird issue

[namoi]

Hi all,

Sorry for this title but I really couldn't find a short way to explain in a few words the issue I am experiencing on my AC68u runing Merlin firmware.

Well, to put it simple I am using Wifi Analizer app on my phone to check the 5ghz channels.
I am the only one here using 5ghz wifi so all channels are empty, but when i activate my router 5ghz band
I noticed the graph display two parabols for the same channel oO.
One got my SSID as it is to be expected and the second one doesn't display any SSID and its Mac is unknow to me.
This parabols kind of randomly appears by growing in strenght and disappears the same way more or less randomly.
Each time I change channel, this "ghost" parabol mimic the change and follow my SSID.
Funny thingh is it's more strong that my SSID in my living room, but when i go near the router it's weaker.

Here is a screenshot showing the issue.

I didn't find any explanation for this, so I would be very glad if someone could help me to understand this behavior.
Thanks a lot

 

[Deleted member 22229]

Do you by any chance have a Roku 3 device on your 5 ghz network ? These devices broadcast there own signal and will follow the router no matter what channel you change it to. This is used for the communication from the Roku to the RF remote.

 

[namoi]

Ah... I got a chromecast. Does it behave the same way?

 

[namoi]

Hmm, chromecast doesn't have a rf...
But i also have an harmony hub which uses a rf remote.

 

[namoi]

Yep that was the Chromecast, thanks @Kal-EL
To be more precise it was the guest network of the Chromecast which was poping up from time to time to check for...well guests i assume. Something that i didn't disabled during initial set up.
After Factory reseting and going through the setup again, I, this time, disabled the guest network and now this annoying network doesn't cluter my channel

Thanks again