Well that's two hours of my life I won't get back. For Artistic Porpoises I was re-working a V5 to show a different name and address. That sort of thing is really straightforward in photoshop, because you can't just put text in a scan, it looks wrong. Instead, should your artistic tendencies lead you to it, you need to create a fill from a like area of text in the scan and use a clipping mask to fill the new text with it. That way, the new text looks the same as the rest of the scanned text. The work of a minute. Except, when I checked the output, it was all to pot, with some very odd artefacts in the text. Never mind, go back, re-work with a different fill. Try smudging the fill. Try all manner of ways. See how bad ordinary text is (ans: really stands out, not a desirable artistic effect). Try, try and try again. Watch things getting steadily worse as increasingly bad output is generated.
And. Breathe. Start again, from scratch. Try a jpg export, why, that works perfectly. Try a pdf export, stuffed again. What's that about?
I suffer for my art.