Hi there Mark,
It feels like the NOS1a not being recognized at this moment. Hence, if you'd go into XXHighEnd Settings and drop down the available devices, nothing of the NOS1a shows and only Motherboard audio devices. Is that so ?
But if you see it, select it.
Btw, apparently you are in Normal OS Mode. Maybe you did that on purpose.
If the NOS1a shows after all, you may fire up the NOS1 Driver Control Panel (the yellow-ish X) and see whether there's life in there (should show "Streaming is up and running" at the bottom). If this is not the case, check these things briefly :
Power cord thoroughly in (both sides);
USB cable in (both sides);
Power switch at the back is on (down);
Sw#2 is on (down);
Sw#5 (the one most far from you) is on (Down).
Lastly, proove that the NOS1a is on in the first place. With the NOS1a this is not so easy. But if you, in the dark, look in the middle section (through the slits) at the left wall, there's a small mirror reflecting the green led which these days is under a PC on top of the DAC board. You will see it shine, when in the dark.
There's also a more easily visible green led in the left leg (~ middle) but if USB fails (like no cable connected) that led will be off anyway.
If this all fails, check the fuses;
Under the power inlet there's a bracket which can be removed by means of pushing the little thingy you'll see automatically. The bracket will jump out a few mm by itself. The bracket will hold two fuses and both must be OK to let the DAC work.
Is one blown (or both), we delivered two spares. If you can't find them, you'll need 1A medium slow blow fuses, and obviously of the same size.
Let us know what happens ...
Best regards,
Peter