Hisense 43H4030f3 Audio flipping between Earphone and TV speakers otherwise great shape

[lfhlaw]

I was able to get a Hisense 43H4030f3 43" TV for free, however, after it has been on for about 40 minutes or so, the audio will start to flip between Earphone and TV speaker mode most likely indicating a failure of a switch, or the audio sensing chip.

I'm just curious at this point, whether it's better to just replace the main board -- at least that's my inclination.
Looking at the main board, I do not see any blown capacitors.

I uploaded a pic of the main board, and a short 22 second clip which shows the issue.

[Davi.p]

In some or all the cases the 3,5mm audio jack for earphone has got internally a bypass contact for tv speakers, when you insert the plug it presses a metal contact that opens the speakers line, defenately it's a dirty/faulty jack