Lookup service??
Look here, I just learned about Gracenote. I was trying to figure out why none of my Linux programs can lookup ID3 info any more. So, now I know.
My only question for you is, what the heck do I enter for my CDDB settings to do a lookup? I have version 2.4.3-lp151.4.5 on OpenSUSE 15.1 / SLED 15 SP1.
Also, kindly put an 'About' somewhere in your GUI. I had to dig just to find the version and this site.