Download links are wrong!

Hey there, after the update the download links for my products are wrong. They all point to the same (but for every user to a different) file instead of different files. I tried changing from forced downloads to another method, but it didn’t work. I also went back to version Woo2.7, to no avail. Something seems to be messed up. I checked with another theme (no difference) and checked other plugins (no difference). Any ideas?