How do I delete them wholesale? And how do I turn it off? I know nothing about caches.
First, make doubly sure that you are indeed working with stacks.
To do that, list your audio files using panes at the top and details at the bottom, not thumbnails.
Right click on a column header and hover over 'Columns'
From the list that appears, scroll down to find, and click on, "Stack Icon"
Click away from the menu to close it.
You should see a column with red and blue icons:
The icons are informative:
All blue means the stack is 'collapsed' (imagine a load of CDs all stacked up in a pile. You can only see the CD at the top)
Red in the middle is shown on 'expanded' stacks. (this would be one of the CDs from the middle of your pile)
Red on top is again shown on expanded stacks and informs you that this file is the "Stack Top" (this would be the CD you saw at the top of your pile)
You can click on any of these icons to expand or collapse a stack.
If you do have these icons on view, then go up to the top of the view where it says "Pane" and hover the mouse there.
A menu will show. Look for "Options"
Hover over that and choose "Expand Stacks" from the menu.
All the files that have the stack member (
) icon can be safely deleted, but as JimH says, be careful.
If you don't have any stack icons on view at all, then it's not a stacks issue and we should investigate further.
-marko.