One of the hashboards is rattling like crazy inside the case.
That's the sound of BTC printing.
Jokes aside, if the above isn't the cause, then it's those channels (where you insert the hash board), you need to make them tighter since they are for some reason (likely the heat) expand and fail to hold the hashboard firmly, maybe put some silicone in them? I know exactly what noise you are talking about, however, I never attempted to fix it because it doesn't really affect anything that matters to me, also what do you mean by the edge of the hash board? do you mean the bottom part?
