Protected PDFs are corrupted on Membership Plugin

My masked PDF links come back to a black page with the text "The image 'http://www.mysite.com/downloads/filename.pdf' cannot be displayed because it contains errors.

Here is what I have tried:
I created a test account with access to the downloadable media group.
I set Protection Method to Basic.
I uploaded 5 pdfs using the Media uploader, set it as protected and inserted it into my page.
I checked the pdfs as an admin and using the direct links to the files they open and download properly.
I logged in as test user in private browser window. I can see the properly masked links.
When I try to open them, I get the aforementioned error. When I "save target as" to my desktop the files won't even open in Adobe Reader because they are "damaged".
I then deleted the files and started the same process over again only using the "Complete Protection" mode... Same results. I deleted the files and tried again using "Hybrid Protection" Mode... still no luck.

??Help Please!