I stopped using PS3 Media Server at some version of 1.70.x. Everything was running great. I didn't change anything on any part of my network, or any software updates when it stopped working.
I followed the FAQs to the letter and nothing worked, over all the subsequent versions. I spent 2 hours trying to get 1.90.1 to no avail.
Until I decided to go old school Mac and toss the PS3 Media Server prefs and low-and-behold it works.
Go to your Library/Application Support/PMS and toss all the config files in that folder.
Works better than before!