I would hope you have already tried all of these things, but I will enumerate them in case there are those who arent used to troubleshooting PostScript printing problems.
This happens in all applications? Even SimpleText?
First, toss all the desktop printers and all printing preferences. Recreate the desktop printers and reset preferences.
Are there any files in the PrintMonitor Documents folder (or its equivalent in AdobePS situation, whatever folder it keeps spooled documents in)? If there are, trash them.
Does LaserWriter 8.7 work?
Those are the basic, quickies I would try first. I am sure that if you've been through Adobe Tech Support, they have had you try all of this, but maybe some folks haven't been through this and would like to know at least one person's way of going about it.