Thanks so much for your reply.
As a baseline test, I booted into Win7 and everything worked flawlessly with the legacy firewire driver.
I went back to Win10, uninstalled the ProjectMix driver and reinstalled it in Win7 compatibility mode. I don't recall if I did that originally. I also found the control panel exe (MAFWCpl.exe) and set it to run in Win7 compatibility mode. Now both ASIO and Windows sounds work in Win10 with the Legacy firewire driver with one exception: If I open a CbB project in 44.1K, windows system sounds stop working. After working in the CbB, I have to go back to the ProjectMix control panel and set the sample rate back to 48K. After that windows sounds work again. I suppose that is acceptable, but I'm not sure why this is happening. Windows sounds should play at 44.1K. It could be a problem if I have to get sound from a browser or another app while using a DAW.
A few questions for you, if you don't mind:
1. Are you still using the Vista driver, 5.10.0.5061? If so, are you still getting crashes?
2. Which firewire driver are you using, TI or legacy?
3. Are Windows system sounds working simultaneously with CbB?
4. Which ProjectMix output are you using for Windows system sounds?
5. What sample rate?
Sorry, to inundate you with questions. I would really appreciate it if you could fill me on these things.
Thanks again.