LG user 42LB6500-TH

Yes - I tried USB as software update was not happening via networks. The disk was not recognized and after multiple attempts, I gave up. I called LG customer care and they said this is a mother board issue and I've replaced mother board. Now the TV is working fine. Thanks!

Yes - all the devices used to work. It is only after the update to 05.05.55, set top box, fire tv stick and chromecast started failing and only dark screen is displayed. I am not able to update the firmware as well to fix this issue.

No app is working for video. Is it an issue with refresh rate between TV and devices?

LG 42LB6500 is having trouble with display. Fire TV stick, prime video and set top box video are not getting displayed and only audio works. It looks like this is a software issue (current version 05.05.55) and I am not able to fix it by updating software to 05.05.70 via internet (image below) or through usb. Please advice.