ESO_GAIN_TO_4BIT
v = ESO_GAIN_TO_4BIT(AUDIO_MAX_GAIN / 2);
lgain = rgain = ESO_GAIN_TO_4BIT(
lgain = ESO_GAIN_TO_4BIT(
rgain = ESO_GAIN_TO_4BIT(
ESO_GAIN_TO_4BIT(