Blue Sound Vault

The Vault does a lot for its price point but the rest of your equipment is pretty good and is revealing the limitations of Bluesound as a digital transport.  Spending a few hundred dollars will get you a noticeable improvement in streaming or playing files from a HD.  My Bluesound stuff sounded best in my mid Fi systems 

Thinking about it further, if I’m you I’d start saving for an Innuos Zen Mk3 that’ll undoubtedly boost your sound quality significantly rather than spending $$$ trying to make the Vault sound better.  They can be had around $2k used, and if you sell the Vault it’d offset a good chunk of that.  If feasible that’s what I’d do.  Here’s an example available now…

https://www.usaudiomart.com/details/649994436-innuos-zen-mk3-1tb/

Thanks everyone for your suggestions.  Steve

Solution that was cheap and enhanced the sound tremendously.  A techie friend suggested turning the volume to max on the Vault.  This allows the preamp to control the volume.  What did I have to lose?  I was extremely surprised by the improvement.  Not perfect but very good.  Thanks again to all   Steve

A techie friend suggested turning the volume to max on the Vault. 

Why not just set it to "Output Level Fixed"?