Text in column changes/adds ;#

In my library i have metadata columns with drop down lists. These have a tendency to change when i for instance edit the filename of a file. See attached screenshot where one entry has the ;# #; inserted. 

The funny thing is that when i changed the filename of all these files, a frew seconds after, all these entries had the prefix and suffix and then they were removed, except for the one.

Anyone have a clue?

added a small vid to show the problem as well