Reports exported to PDF displaying images as black background

So we switched the images from directory paths to files over to grabbing them from a db. Except now it seems that when the reports are exported to PDF the images keep having a black background.

I've tried PNG & JPG. I've tried Transparent background PNG and Solid white background PNG I've tried White solid background JPG

I've tried CMYK and RGB for both. The MIME-type appears to be set correctly.

Except it still keeps displaying the images with a black background. The overlaying actual logo image and text displays fine, but the background of the image itself just keeps displaying as solid black.

Can somebody save my sanity and shed some light on this mystery? I'll admit I'm not a big SSRS guy.