Help! I have a Sansa Fuze and i have been having a lot of problems with it!

I put video on it with the converter.they worked,but then the mp3 player froze on one of the videos.i deleted them on the internal memory when i plugged it in.Then Music started showing up as doubles.I deleted 1 of the doubles and then the other stoped working.I plugged it in and deleted.I added music again and kept cycle until it was only 1.Then other songs on there disapeared.I added them again.Then i couldnt add music at all.All folders in internal mem doubled and music folder was gone.I figured out how to swich modes.I could then add music,but the music didn’t appear in the folder.Whats wrong?Oh and i purposfully misplelled b/c w/e i typed this, it always exceeded 100 char. 

Were your albums ripped on a Mac?

MacOSX rips both songs (01-FirstSong.mp3) and little 0kb finder files to direct the Apple operating system to the songs (_01-FirstSong.mp3). See the underscore at the beginning of the finder file?  Maybe those were your duplicates .

Your computer can only see one mode at a time. Anything you add in MSC is invisible (to your computer) in MTP, and the other way around as well.