Very slow load of content in "browse" tab

This problem may be related to the issue in 1.4 where the Library tab doesn’t work at all when you have a very large amount of music.

When I click on the “Browse” tab, the main directories load up fine - I will see the NAS and WEBRADIO etc .directories.

Clicking on one of these, though, produces a very long delay before the browser loads the selected directory. The delay can be as long as 15-30 seconds! At first I thought the browse function had completely broken, but then I realized it just takes a very long time to load the content.

For reference, my library size (using the very excellent library organizer beets, which I strongly recommend):
volumio@volumio:/var/www/css# beet stats
Tracks: 40432
Total time: 17.7 weeks (10700190.17 seconds)
Total size: 422.4 GB
Artists: 5724
Albums: 3274

I’m having a similar problem in version 1.5. Have you made any tweaks to try and fix this?