If you have any of the older versions of the sounds when I used to use all the different soundscripts for each separate sound you have to delete those soundscript files. Everything has been consolidated into the gravedigger.soundscript file now and will interfere with the old scripts. Look in your v4 pack and if it contains the soundscripts named Collector2, Downsweeps, Mufflers, Sidepipes, Zoomies, Powerstroke or Powerstroke60 you need to delete those. This has really turned out to be more of a pain than anything releasing these because it doesn't seem to work the same for anyone. And as always feel free to skype me with any questions.