You have suggested that I don't know how my voting process "actually works", and that I cannot know that without volunteering to help run an election. I do not agree with your premises. Furthermore, that's an ad hominem argument.

The black box I am referring to specifically is the optical scan vote tabulator machine that sits between me and the ballot box, in my current polling place. I have seen it multiple times, and examined it to the extent that I am able. When I lived elsewhere, there were different machines. Every one of them has been a black box to the voting public.

I very explicitly do not trust those machines, because I know how the grey boxes that build the black boxes typically work. The publicly available information about them does not inspire trust. They are defective by design, and stink of corruption.

Some places do have trustworthy elections, using publicly-observable hand-counted paper ballots, like in Minnesota; or slightly less trustworthy vote-by-mail for everyone, like in Oregon. Good for them. I have never voted in those places. Bad for me.

And voting does have an authority that can "fix" things. It's usually the secretary of state for the state, then the supreme courts for that state and for the US. I remember when the SCotUS threw the PotUS election to GW Bush by interfering in Florida's lawful elections process. They didn't back up the voters' authority in that instance. I have felt the frustration of statewide elections where I had a sense that someone was dicking with the results, and there was nothing I could do about it without putting so much effort in that I'd be turning elections activism into an expensive, thankless hobby.

I have zero trust in the current US elections process, and never believed that my vote actually counted for anything. I honestly don't know why I keep voting--gesture of defiance, maybe. I think the voting systems in every place I have voted have all been broken, from the enabling legislation all the way down to local procedures at the polling place. First-past-the-post is broken mathematically. Ballot access laws are cheating. Gerrymandered district boundaries are cheating. Restricted primary voting is cheating.

I can't do anything to fix the systemic flaws without spending 20 years becoming the controlling authority of a single-issue political bloc and fundraising it all the way to actual significance, but encryption math and open, publicly-auditable software is a lot less work, and could still help with the local procedures. Of course, we'd also need a trustworthy compiler that can produce bitwise-identical binaries of different machines, and a trustworthy computer to run the compiler on, and some way for the public to verify that the software running during the election is the same software that was compiled at the public ceremony. And then also assume that an attack on integrity might still succeed, and proceed under the assumption that the system is compromised, whether by intentional act or accidental mistake, by auditing the final results in a non-predictable way.

Buuuuuut... it's not really my job to restore trust in the system. That's up to the ones profiting from it. I have named a system that I, personally, could possibly trust. But it will probably not be adopted, because the trust comes from the tamper-resistance, and elections tampering is a feature desired by those currently holding elected office. In my estimation, voting in the US won't be fixed within the next 5 years, because there is currently profit to be taken by keeping it broken.