If this is hardware (I don't believe it for a second) then Hisense owes a lot of people, a lot of money, and a massive recall.
This issue is too specific, in my opinion, to be hardware. We've got the same reports, of the same issue, at the same time, even for brand new tvs. This sounds like a firmware update error to me, especially because there's literally nothing wrong with the speakers in question. The hardware works with menu-related sounds, it has to be software. I don't see how hardware from numerous customers all fail the exact same way, at the same time, without actually having the speaker go bad. It makes zero sense.
I think the next step is to remove internet access to the tv, then factory resetting it so it cannot update, and assuming we can actually use the inputs in that situation, see if the problem is fixed in its default, non-updated state. If it is, it is 100% firmware.
I don't want to have to go through all that to find out, but if it's the only option I have to make a further report, I'll do it.
