itunes duplicating songs when adding

I'm having an issue with itunes on my Mac (windows version doesn't do this) Almost every time I add an album to itunes it will duplicate most of the songs. For instance if I have a folder with 15 songs and I drag it to my itunes icon or if I go to file - add to library, itunes will duplicate a majority of the songs so that instead of the 15 that are in the folder I get about 25 (10 duplicates) Its frustrating to have to constantly clean up after adding albums.

I have itunes set to copy when adding files so that i can just drag several albums from different locations and then delete them.


Any suggestions?

I might be presuming a little bit too much here, but if the music is downloaded from the internet, a lot of the time, the folder will contain a .m3u file. Which whenever i accidentally add to the itunes, it usually copies most if not all the music in twice.

Yes, this file does appear often. I'll make sure to delete that file from now on. Thank you.