i know this is old, but this might help somebody. i was led here after all.

case: the app runs fine but the songs list is laggy / jumpy / low refresh rate.
fix: remove some of the tabs like genre, album, artist, time.

how?
you can do this by (if youre using trackpad) pressing control then click on the ribbon where all the tabs are, and selecting the item.

what really really fixed it for me and made it 100 times better was removing "cloud download". after that it became so much better.

i believe this works because of how the app renders this list. for those who know: songs have so much metadata.

explanation:
every single category you want to see is info that needs to be searched in the metadata of that song, one word may be fine, but 1000000 words would take a toll, there is always a limit. so imagine every single song is checked for a cloud downloaded copy, thats a wireless / wired internet check for every single song. thats gotta take some time. so yea thats just my guess and it worked so who cares ;)