@CherryStraw ah thank you, that makes sense! Thanks for clarification.
I thought it shows if it's Flac or what the audio file was created from, like CD, Vinyl,... the CD icon confused me Therefore I never thought about the actual source of the files (like Hard-Drive, Network-Share,...).

I've only been using this software for a short time and I think it's great!!
I wonder what is displayed in the Source column. There is a CD symbol for all my songs. What tag do I have to set for something else to be displayed here? What other sources are there? I have not been able to find any information on this so far.
( Sorry if that's the wrong category for the question. And excuse if that's maybe a bit of a stupid question, but I'm not good at reading code :D)