Glad you received it in one piece. It was made and probably also burned in before you ordered, so it does have 100 hours.
Are you connecting the dac19dsp to the brightest amp you got? There's certainly some "dark" when I don't plug my dac19mk3 into my quite bright power conditioner, but there's something easy you might be able to do about it. Are you plugging the dac directly into wall outlet or a surge protector/power strip? It should be better if you connect directly to the wall with a thick power cable, or the stock one that came with the dac19dsp.
Do you still have your custom pro 900 copper cable btw? I recommend putting it on the pro 900 to enjoy the tight bass of the dac19
. One last thing, if you're using the computer are you using a bit-perfect media player?