Surfans not labeling consistently

Hello,

I have a Surfans v3.4 and it mostly does what I need. I like to play songs by album and will change a bunch of songs to one album so they all show up together. Like "Pop Mix" for example. However, this only works for 90% of the songs. Even though I have coded them all in mp3Tag and File Explorer Properties to all have "Pop Mix" listed for the album, some of them will show up with their actual album title in Surfans, even though that data is not part of the file, at least that I can see in mp3Tag and elsewhere.

So why are these 10% of songs so stubborn, and how can I get them to show up in the album "Pop Mix" with the others - which is how they show up in my computer? Thanks for any help you can provide!