Sorry, missed your post.
This is one of the challenges making volumio available on x86es, there are ten thousand different configurations out there.
We will never cover them all.
Did you already add your own drivers? If yes, where did you get them from, if not, I need a bit more info on the hardware
On second thoughts, there is an issue with wired, it is being sorted at the moment.
Wireless currently starts in hotspot mode (as far as your wifi module supports it), an option to switch it off is also in the make.
I have no worries with your DAC, usb audio is supported ootb and should not have usb issues as know from several arm devices
As for your broadcom wireles, you can try to install the firmware:
Get a ssh connection (uid=volumio, pwd=volumio)