PDF wont print from Layout - "flattening" issues

Using a .jpg background for 24"x36" board. Lay text and graphics over it and send off as PDF.
When trying to print PDF, Acrobat gets hung up at 43% while “flattening”- spins for about 2 minutes and quits. If I remove .jpg it prints fine. File size is 6mb. Any thoughts?
Layout 2019 on PC windows 7

It is a typical Acrobat problem with overlapping objects on a page. I have often seen it with AutoCad and Archicad too. Probably the page is too complicated for your printer to process. My solution has been to export the page as a PNG image file from Acrobat and to recreate the PDF from that. In the depths of Acrobat print settings there would also be a “print as an image” checkbox that you could try.