Audition Panels resize every time I open the program.

Have you tried resetting Audition's preferences?

It could also be that the folder containing the workspaces isn't writable by Audition.

On Mac:

1. Open Finder
2. Press Shift+CMD+G
3. Paste in this location (replacing the variables in brackets): '/Users/[username]/Library/Preferences/Adobe/Audition/[version]/Workspace/Saved Workspaces'
4. Right-click on the Saved Workspaces folder and choose "Get Info" or press Cmd+I.
5. Expand the "Sharing & Permissions" section.
6. Click the lock icon at the bottom to make changes.
7. Select the "Everyone" row and choose "Read & Write" from the dropdown menu.

On Windows:

Follow these directions https://www.thewindowsclub.com/change-files-and-folders-permissions-in-windows-10 on the Saved Workspaces under 

• C:\Users\[UserName]\AppData\Roaming\Adobe\Audition\[version]\Workspaces\Saved Workspaces

It saves the new workspace, but the same problem persists with the panels resizing.

Have you tried saving using a new workspace name?

When I do, I get an "Audition Error" message that says "Audition has encountered and error. A workspace with this name already exists." I've tried deleting the workspace and re-saving, no joy.

Do you save the reset changes?