[Roy Dennis]

When you rebuild the database it builds it from the list of folders showing in the bottom left window.
If you have the folder listed there that had your original mp3+g files on that you imported as kma files then that is why you have these duplicate files showing.
So I'm assuming when you imported them as kma files you would have selected a folder just for those and the original files would still be in their own folder.

If you look down the list of folders try and determine which is the folder you imported the kma to, then select the other or others and choose the Exclude folder button, this will remove all the songs in those folders from the database and also stop it re-listing those folders in the rebuild list.

If you make a mistake you can always remove them from the Excluded folders list and Re-Add to the rebuild list.

Alternatively If you recon all the HDMP3 are files that you did not intentionally import you could just delete those from the edit dialog.
To do this open the edit dialog and select multiples button, select all the top row for match items and karaoke for bottom type.
Enter the wild card character * in the Match window and press find, this will list all your karaoke types.
Now click on the header for Type, this will list them all in order of type, then select the first one in the list HDMP3 then scroll down to the last one of that type and use Shift+left click will select all of those songs, it may take a little time to highlight them all but once your happy the right songs are selected press delete.
One word of warning,doing it this way is not reversible.