Superman Album Art not detecting all albums

Been dealing with retagging and getting album art working. I seem to now have all albums tags coming up correctly. I just convert all tags to id3 v1 and v2. Is there a better way to be doing this.

But then I noticed in Superman, out of about 50 albums (259 songs) there are a few albums that won't show up -- thus I can't easily download album art. I know how I could manually download and rename the .jpg to show up in meizu, but I'm wondering if other people have noticed this issue with Superman. It's a really great little app, and since it works for the vast majority of my songs, my guess is that it's something with the id3 tags.

Any help is much appreciated.

This happen when the tag version is ID3V1 instead of being ID3V2.3
I use Mp3tag - the universal Tag Editor (ID3v1, ID3v2, APEv2) to do the job.