Does socket orientation have an effect on sound?
I can think in one effect but only for a very specific hardware. If You're using a capacitive supply with a half-wave rectifier - In this case the circuit ground is connected directly at one of the socket pins. If this pin is the ground its ok. If this is the 220 AC, although the circuit still operates, you may have some noise coupled on the circuit via ground, as your new ground is oscilating at 60Hz with a amplitude of 220 volts
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