Ur24c. standby mode? power state recomendation?

I have ur24c with linux laptop, and no any official drivers or soft installed, but device work as plug&play. connected and powered by usb 3.0.
When laptop turned in suspend/sleep mode, the led continues lid all the time. Is there a standby mode or any energy saving mode on this device?
If there is no above-mentioned mode, should i manual turn off device by power source toggle?
Thanks for answer.

This must mean that the USB port continues sending power to the device. I’m not a Linux person, but I would presume there are controls for power over USB in the OS.

As far as I know, there’s no hardware sleep in any audio interface.

Thanks, i’ll try to control usb power.

It’s most probably a “feature” of your laptop to keep providing charging current while it’s asleep (meant for a smart phone for ex., not useful in your case).
Dell calls it “PowerShare” - you can disable it from your BIOS menu.

If the above solution does not work out for you, you can flip the “Power Source” switch to its “5V” position. If the wall adapter is not plugged in, this will effectively power off the unit. (just remember to flip it back to the “USB” position when you wake your laptop.)