Regarding this question, I will answer you.
Even if USB/SSD Power activation in standby mode is set to OFF, the power supply is not cut off immediately in Standby mode.
However, in Standby mode, RS150b gradually loses power within 5 minutes.
The power supply is not completely cut off. If you set USB/SSD Power activation in standby mode to OFF and switch to Standby mode, 5.87W of power flows. Even if the power is turned off completely, the power of 0.3W is maintained as long as the circuit and cable are connected.
Set USB/SSD Power activation in standby mode to OFF, switch to Standby mode, wait 5 minutes and let us know what happened.
Thank you