Your screenshot shows that you have modified the default High Quality preset. What did you modify? I compared your compression tab that you showed to the default for that preset and don't see any deviation there. So could you either say what has been modified or post screenshots of the other tabs of your Export Adobe PDF dialog so your full process can be shown?
The image comes from Illustrator. Don't place a PNG, place the AI file.
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I called adobe and they helped me, the answer was that the downsampling.
Should look like this not, Bicubic which is the standard setting.
Thanks all for your help!