From the soundbars manual.(page 15)
AUTO POWER On/Off This function automatically turns on/off the unit when you turn on/off the TV or the external device (DVD Player, Blu-ray Disc Player, etc.) connected to this unit. It is supported only on OPTICAL and LG TV functions.
This function turns on or off each time you press AUTO POWER ON/OFF.
After the unit is turned on by AUTO POWER function, it will be automatically turned off if there is no signal for a certain period of time from the TV connected by LG Sound Sync (Optical/Wireless).
After the unit is turned on by AUTO POWER function, it will be automatically turned off if there is no signal for a certain period of time from the external device connected by an optical cable.
If you turned off the unit directly, it cannot be turned on automatically by AUTO POWER function. However the unit can be turned on by AUTO POWER function when optical signal comes in after 5 seconds of no signal.
Depending on the connected device, this function may not operate.
In Bluetooth mode, this unit may be turned on by AUTO POWER setting depending on the connected Bluetooth device and then LG TV function is selected. In this case the unit will be turned off automatically and when you restart the unit, it will be turned on by LG TV function.
LG NB2540 Support: Manuals, Warranty & More | LG U.S.A
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