nemilose

It might be something related to HDMI CEC option. If there is such an option in cable box setup, try to turn it off.

Did you try to format it to NTFS?

https://www.lgwebos.com/applications/tapatalk/index.php?/topic/3054-HBO-Go

It is DisplayPort to HDMI adapter.

Why don't you connect a computer with the TV?

You need something like this

Probably 1.0

It is WebOS 3.0.

You may try to export channels list to USB, use ChanSort to sort them, and import the list back to TV.

I do not have this model of TV, but you may look for an option in accessibility submenu that allows multiple audio output. For example, newer Samsung TVs have an option that allows to use both internal speakers and Bluetooth headphones at the same time: http://www.tomsguide.com/answers/id-3209250/headphones-speakers-simultaneously-samsung-smart.html

I have UH8507 and the available internal storage is 0.11/0.62 GB. However, if I go to LG Content Store and click on some application, it says that the available internal storage is 463/631 MB.

In that case it is a WebOS 3.0 revision. To the best of my knowledge it will not be upgraded to 3.5 or higher. I think it is due to hardware differences between the chipsets.

It is probably firmware version.

UH TVs have WebOS 3.0. You cannot upgrade it to any higher version.

Try to change WiFi channel. The best option is to temporarily run a LAN cable to your TV, so you can check whether the problem is related to the WiFi connection or your ISP.