<p>There's an error on the board marking of C5. C5 is connected to the audio input signal.<br />
The positive side of the cap should be at the bottom NOT at the top. If you put the cap in the way it is marked on the board, the input signal will be distorted or intermittent or just not work at all. Flipping the cap should fix this and the input will work fine.</p>
<p>UPDATE!:</p>
<p>If your board says V2.1 on the back, do not worry about this, install C5 as you would normally, with the long end going through the square hole!
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