So, in paperspace, you are showing the raster image you inserted in model space via viewports? Or are the images in paperspace only?
Either way, is the image referenced or embedded? AutoCAD (and therefore TrueView) only supports referenced images. In essence they are treated like Xrefs.
First I would Try different toggling the embdded/referenced property.
Then I would try and creating a block for each image and inserting the block at the required location - this may insulate the image from the scaling issue.