My office is also having major problems with this. Now that Marsy's Law is in effect, we have to redact soooo much information from our police reports. These come from many different agencies using different software to create their PDFs. It's ridiculous that it is happening so frequently across so many different agencies' PDFs. The only thing I have found to get around it is to remove just Objects from the Remove Hidden Information section and re-run text recognition on the file. It noticeably diminshes the quality of text in the PDF. Adobe needs to fix this.