Dambor

I have issues with the library mode. Library takes about 5 min to load in my iMac. The app also takes about 2 mins to load the data and when you toggle from (say) artist to album views, another 2 mins. No issues whatsoever if in itunes integrated mode and SQ great in both modes. My >2tb music library sits on a Synology NAS, my iMac runs Yosemite latest version, my iOS is 9 and my router is an airport extreme. How could I fix this? Any ideas?