Hello,
Did you get to solve this issue with your TV?
I have the same model LG TV that started showing the exact same problem last week (on 6/25/2017). Interestingly, your post is also dated during that time. Please let me know if you have any information on this. Thank you.
I noticed yesterday that my captions were blurring. When I sat down today to watch a show, I noticed it was because the bottom part of the picture was shifting just a tiny bit up and down.
A few months back this same TV had the black screen/still hear sounds issue, but after taking the tv apart, poking around, and plugging it back in... it fixed itself.
Just wondering if anyone's had this issue and had fixed it themselves. =) Thanks in advance.

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