Isn't there a conflict of interest when members of the Fed are also owners of large companies and investment banks that directly benefit from controlling monetary policy
Yes but I think congress vettes people to make sure they don't have huge shares in these companies. Most members of the board are not rich enough to own a bank like Goldman or Bank of America, in fact the big banks are almost exclusively owned by mutual funds not by individuals.
Also, I'm not an expert...or even terribly informed, but what is your definition of audit? It doesn't seem that they are were eager to reveal who they were loaning money to in the wake of 2008.
They are regularly audited by contractors hired by the treasury every single year, its not like the Executive Branch doesn't know what's going on. What this audit the fed would be about is having the American people let in on the inner workings of the Fed rather than just top State Officials and people at the Treasury.
It is rigged and it is fucked up that former JP Morgan and Bank of NY Mellon directors can then go on to manage the monetary policy of the state of New York and by proxy the whole country. But the biggest problem is the banks themselves and the very idea of capitalism not the Fed which is just a vehicle for regulating the markets and keeping credit flowing through the system which is what keeps the economy alive. With this many businesses, this many people you need banks and credit or you are fucked. Now an anarchist society does not need banks or credit but that is a different story. A property rights based, money using society absolutely must have banking and government regulation of the money supply. The reason the Fed is partially independent is to prevent governments to do what the Wiemar Republic did and use money as a political tool to buy people's favor. This is actually what Bernie is sort of doing as he wants to massively increase inflation and give out huge sums of tax payer money to people without thinking about the long term financial consequences at all.