Pioneer SX-939 Operating Instructions Manual page 16

duced in hi-fi acoustic units result from external
sources of noise: Due to the inherent high sensi-
tivity and the high fidelity in reproduction, the
unit amplifies and reproduces extraneous noises,
however small, into definite output noise. If your
receiver produces a noise, check according to the
following table and trace out the source of noise
for the appropriate corrective action.
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