One thing you might want to look into is whether the W4S uses power from the computers USB port - many DACS take this approach.
I found a dual USB cable where one cable handles just data and a second just power - they are joined at the DACs usb plug.
I now power my DAC's USB board from an external power adapter.
The improvement was quite noticeable.
The cable itself is very good quality and improved on my DH-Labs USB cable - even with both cables plugged into my iMac.
Other USB power solutions include the AQvox power supply which injects cleaner power into an adapter that fits between the USB cable and the DAC socket.
Personally, on my Bifrost I was unable to tell the difference between USB, SPDIF and Optical inputs. But I think the dual cable and seperate power supply upped the anti in favour of USB implementation.
Regards
I found a dual USB cable where one cable handles just data and a second just power - they are joined at the DACs usb plug.
I now power my DAC's USB board from an external power adapter.
The improvement was quite noticeable.
The cable itself is very good quality and improved on my DH-Labs USB cable - even with both cables plugged into my iMac.
Other USB power solutions include the AQvox power supply which injects cleaner power into an adapter that fits between the USB cable and the DAC socket.
Personally, on my Bifrost I was unable to tell the difference between USB, SPDIF and Optical inputs. But I think the dual cable and seperate power supply upped the anti in favour of USB implementation.
Regards