Pioneer A-40AE Manuel D'instructions page 19

"Speaker impedance settings" (p15)/ "Switching input
and adjusting the volume" (p16) / "Adjusting the sound
quality and balance" (p18) / "Setting auto standby"
(p20)
0 When switched to power amplifier mode, if the volume of
the connected pre-amplifier is low, auto standby (p20)
may function and the power may automatically switch to
standby. If this happens, you may be able to fix it by
increasing the volume on the pre-amplifier.
0 Also read the instruction manual of the pre-amplifier you
connected to this unit.
Basic Operations
19
En