I'm writing to thank the posters frenkygo and alterniTech and many others before them for all their insite into this problem. I have an OLED65B7P which has been displaying intermittent problems with the magic remote (mainly the bluetooth enabled functions), with the frequent pop-up "wired lan cable disconnected" messages, and with hesitation of images on streaming while using ethernet connection, and on having no WiFi function at all (No way to turn on Wifi). These communication issues recently culminated in most streaming and bluetooth functions failing almost completely.
After reading this entire thread, plus a few others found elsewhere, plus viewing a few videos on the subject, the solution that made the most sense to my mind is that the connector that connects the ribbon cables to the wifi module had suffered oxidation and connections that are noisy or broken. I have some training and experience in electronics, and the other potential fixes did not make it through my mental filter as making much sense. However, a bad connection on a critical high speed communication port, like the one to this wifi module, can have the effect of confusing the main board comm controller firmware, and causing constant interruptions thereby using up processing bandwidth. In the final stages of my problem, I even noticed that simple commands from the remote, like MUTE, were responded to very slowly, which reinforced my opinion that processors are overloaded with interruptions.
I also assumed that Bluetooth was also handled through the Wifi module, which would explain why I could no longer register my remote.
This solution is also consistent with those that fixed their tv by unfolding the ribbon cables because those folds are very close to the module connection, and the process of unfolding these would certainly jiggle this tiny connector enough to clean up connections through the wiping action of the internal contacts. Any slight movement of the connector relative to the module is likely to clear the problem. To my knowledge, I don't believe that those folds are the fundamental root of the problem. Their performance and behaviour is unlikely to change over time, and since the ribbons are shielded types, they are not likely to interfere with each other any more after a couple of years than when they left the factory. I may be wrong on that, and to be sure, I also unfolded my ribbon cables. There is no downside to doing this as long as you don't cause those ribbons to be caught between things on re-assembly.
While doing the fix, I attempted to brush the connector pins with isopropyl alcohol and push the connector in and out at least 5 times. The connector is tiny, so its hard to say if the alcohol helped. I have no idea how long this fix will last before oxidation once again rears its ugly head, but confident that a half hour of minor surgery can fix it again.
To sum up, my TV is now working perfectly. The magic remote registers immediately and performs as new. Hesitation on streaming sources is gone. I believe that this has also cleared the problem of the popup messages "Lan cable disconnected" followed by "lan cable connected", but need to give it some time for proof. I think all problems have all been eliminated.
Edit: Jan 3: Yes indeed the recurring popup messages about "lan cable disconnected" are gone.
