8.4 music not organizing properly

I updated my 6 Plus to 8.4 when it released and was enjoying the slick new Music app as it had fixed some issues that were not allowing me to update artist info by syncing my phone. However, today, for no apparent reason, certain artists are no longer being organized properly in the "sort by artist" view. I have a large collection of Korean music, but since all my system languages are set for English, I have spent considerable amounts of time converting Korean track and artist names to English, or filling in the "Sort By" field in the data editor so that they will be shown alphabetically. These changes are all reflected without issue on iTunes (12.2.0.145), but my phone seems to be ignoring the "sort by" info for certain artists, or in some cases, has somehow reverted the English names back into Korean. This results in Korean artists getting clumped up in the "#" section of the of the sorting field making it hard to find the artists that I want. Artist names are displayed and organized correctly within the playlist view on my phone, but without the jump-to slider on the side, it is still quite a clumsy way to search for artists. Force closing the app and hard resetting my phone did not make a difference, nor does resyncing to (the correctly organized) iTunes. Any help would be greatly appreciated.