Stamps change size after compression despite using Preflight to flatten

I have a glitch where sometimes (rarely) after I place a stamp on a document it will populate perfectly and I can save the document and it is as desired. I will then go to Preflight and use "Flatten Annotation and Form Fields" to analyze and fix the document. Finally I will compress the pdf, whcih upon completion of the compression leads to the previosuly perfectly placed stamp to suddenly gains white borders around the stamp's borders then cover the majority of the page making much of the document appear blank. Is anyone aware of what could cause this problem?

From my understanding after the Preflight the stamp shouldn't even have data to be modified and is a static 'part' of the document. I do know that the stamp is placed as a png (allowing one to move and stretch), but after the flattening, the stamp is converted into a part of teh document and is no longer a seperate png item that can be modfied and can no longer be moved, stretched or deleted. Could this be an issue where the preflight is not doing what it is supposed to resulting in the compression misidentifying the stamp/png as a page and adding borders to size it correctly? This is just my theory but I would greatly appreciate an expert's opinion!