PDF Fading when embedding PDF

I am trying to embed a PDF file into my Photoshop file. I have done this many times previously and it has worked fine and now for some reason it comes in faded.

When I first click place embedded and pull in the file, it looks like this, which is what the PDF colouring looks like when open in acrobat:

However, as soon as I hit enter (commit transform) it looks like this:

I assume I must have changed a setting somewhere down the line but I can't figure it out! Grateful for any help which can be provided. I have tried adding a stroke and editing it in Photoshop but this obviously isn't the ideal solution.