KHP4 running slow

[is14fun]

I was using the program and completed several projects when the program started acting up. I edited the lyrics and when I played the screen, the highlighting was way out of sync. I tried to redue the song, but each time I do, the sweep is maybe 3 to 4 seconds late. I rebooted but that did not help. I am running XP home on a HP Pavilion zd 7000, 512 ram with 5.2 gigs of free hard drive space. I remember something about temp files and maybe they need to be empied. Program was working fine up to this point. Any help would be welcome