For that album, try this. Delete the folder.jpg file and then in dbPoweramp metadata editor, click on the Choose from internet button. That should find a 1400x1400 resolution image from PerfectTunes so click on that then click on the three dots next to the Choose from internet button and resize art to 800x800 and see how it looks in the app. That’s what I do with all my rips. I don’t have any folder.jpg files, the art is all embedded in the flac files