@APLH  If the USB peripherals you're referring to are connected to the dock rather than the system itself, then I think that behavior is actually managed by the dock firmware, which is designed to keep USB peripherals attached to it powered when there's also a system attached to the dock.  That enables features like Wake on USB for people who want to use that, and it would also allow peripherals that are charging their batteries that way to continue doing so.  Sorry you consider that "rubbish design", but I don't know of a way to configure the dock's power management.

Thanks for the reply.

I guess it depends how you view the dock. For me, it is an extension of the laptop, so when that goes to sleep, I also want the peripherals too otherwise they are permanently on as they do not have an auto-sleep function. I'm not sure why it has to be in full power mode for Wake on LAN? My NAS isn't and wakes from the router's instruction. Anyway,  you're saying that is how it is designed so I guess I am stuck with either shutting down or pulling the power lead out the back.

Also, I find that unplugging my MIDI keyboard and then plugging it back in causes my DAW software to 'think' it is a new device every time so I have to constantly configure it. Any ideas why this is happening? Only started since plugging it into the dock.

Thanks for your explanation.

@APLH  if your NAS can wake on LAN, then its Ethernet controller has to be kept active at least on some level, even if the rest of the NAS is asleep.  Similarly, if the dock is going to support Wake on USB, then its USB controller needs to remain active, and it also needs to continue providing power to attached USB peripherals because the USB devices that one would most commonly use to wake a system (namely a keyboard or mouse) would not be connected to external power; they would rely on power provided from the USB port.  As a result, if the dock's USB ports were NOT providing power, then the keyboard and mouse (or mouse receiver) would not function, and thus it would be impossible to use input from those devices to wake the system.

I'm not sure what to suggest on the MIDI keyboard front since I've never really used a MIDI keyboard and I don't even know what DAW stands for.  I remember years ago sometimes plugging a device into a different USB port could cause it to register as a different device, but that doesn't seem to happen anymore, and if you're seeing this behavior even when using the same USB port on the dock, I don't know what to suggest other than maybe keeping an eye out for BIOS updates to your system and/or WD19TB firmware updates that might be released in the future.