Using the Bluesound or DAC for volume control usually leads to bit stripping. Some DAC have a good volume control. I don't remember what kind that is or what brand DAC has these.
Affordable GaN FET amp from Peachtree Audio
Peachtree Audio is offering a Beta Test program for their new GaN 1 amp (not to be confused with their GaN400) and it's being offered at a substantial discount ($1299 instead of $1999) just for being part of the Beta Test group. It has only one digital coax input and that's it. 200 Watts/channel, zero feedback, and no DAC since the GaN FETs handle that.
All the best,
Nonoise