UPDATE: IT WORKS!
RME guys, Mathias: IT WORKS!! Fireface 800 WORKS IN VENTURA AT RELEASE TIME!
I am sitting here looking at Totalmix and Fireface settings, and playing a playlist in Apple Music (I still call it iTunes lol). System audio is set to FireFace 800 and operating quite smooth, just as before (I was on Monterrey up to an hour ago, and now am on 13.0 Ventura).
So, I should restate my signal chain for anyone reading this -- because I am absolutely *NOT* using Apple's "Thunderbolt to Firewire" dongle thingy. I am using a Thunderbolt PCI Express Chassis with a TI chip-based Firewire 800 PCI-E card in it. From there, it's just Firewire 800 cable (very high-quality cable) over to my FF800. From there my FF800 is connected to a Dangerous Music D-Box --> Yamaha HS-50s (and various headphones) for listening.
I have never had 100% reliability with the Thunderbolt --> firewire dongles, but the PCI Chassis approach gets it done, every time. Trust.
And Apple left Firewire in Ventura!!
I am now going to turn up my music, sip a Cognac in celebration, and go to bed.
Enjoy the good news folks, Firewire is still on the (Ventura) menu... and boy am I happy.
RME you guys built a helluva product, and it's extended yet another year in the Apple world.