How would you improve the sound of Squeezebox?

I've been listening to my Squeezebox for the past week running through the Monarchy DIP upsampler into the DAC of my Opus 21 and I'm convinced the Monarchy is an improvement using the 24/48khz output setting. I tried 24/96 and didn't care for that setting - the music became thin and edgy. At 24/48 - compared to no DIP - the backgrounds seem quieter and music just seems fuller and "cleaner". I've swapped the DIP in and out of the chain several times for comparison and I comfortable the DIP is an improvement in my system. My listening is entirely with internet radio and Pandora. YMMV, of course.

Give her more chocolate and flowers and take her to
the movies more. Oh, yeah...take her out friday nights.

I listen to both CD (wife's mandate)and a NAS based flac files. I placed EA Pace Car between both my traditional transport and SB3. Pace car connects to my Northstar 192 DAC via I2S connection. Pacecar definitely cleans up a CD or or music files from a server. I definitely notice more resolution as I can start to locate individual instruments in a large band or orchestra. I wouldn't say the sound stage got wider -- I would say I hear more depth as I can recognize more layers from front to back. I guess some people would call this holographic. Anyway, EA Pacecar does that for you. My SB3 is only modded to "communicate" to my Pacecar and is stock otherwise. I even have the stock wallwart. I just doesn't matter what comes out of the "transport" as long as all the bits are there. Pace car will reclock and feed your DAC with synchronized file.

I've just swapped out my SB2 for an SB+ from At-Tunes. I did have the SB2 running through the Cyrus dacX which did make a big improvement, however Patrick assured me the Dac in the SB+ was as good so I sold the Cyrus before I could do a head to head comparison. I personally enjoy the extra detail a good dac can bring so am looking to add a Bel Canto Dac3 or possibly a Dodson to my SB+ when funds allow.