I currently am using my Roku Express 4k on a 24" Lg smart tv (2018). What I find is that if I unplug the Roku for a couple of hours and plug back in it works for all channels. I can tell it will work when the right side screen near apps is showing info. During the day I may turn off and on the TV 2 or 3 times before it will not load completely. Very irritating especially when wife wants to use and it fails.
Here is some info :
Roku Model #3941X, Roku Express 4K+, Serial #X01600015TFX, Device ID 507P2211STFX, Software Version 14.0,
Does it occur on a specific channel.....Spectrum TV app Version 13.6 build 0 (Up to date)
My wireless connection shows 100% Excellent, Wireless channel 48, My network address and password have been checked multiple times.
I also use a Roku 4k Express + in the family room, this particular Roku is used in the kitchen on a 24" LG smart TV with 2 HDMI's. I have tried both HDMI's and both act the same.
Bill