I am of the opinion that audio over Firewire may be an afterthought in modern Windows.
 
I am using an end of life M-Audio FW-410 with Win 7 drivers that still work on Win 10.  No hope of ever getting an update, but it still works.  Although I have had a few head scratchers getting my DAW and Windows audio to co-exist...

I'll chime in on this one.
 
I too have a Focusrite Saffire interface running ASIO.  IMO, Windows 10 continuously and needlessly screws with the PLAYBACK DEVICES sample rate.  I need to stay at 48kHz, and Win10 likes 44.1kHz despite being selected in the menu to be 48kHz.
 
I guarantee that when your audio is lost, and there is no sound, you will find your PLAYBACK DEVICES set to 44100Hz.  Usually you can set it back to 48000Hz (or whatever rate you're using) and get the sound back without delay.  However, sometimes it completely borks, and your options will be unavailable.  It's locked up and the PC will require a restart.
 
This is one of the biggest annoyances I have with Windows 10 for audio-related stuff.
 
Additionally, Win10 likes to sneak in additional audio drivers on ya.  For example, I have my motherboard's audio DISABLED in the Device Manager.  Also, my monitor seems to have an audio driver despite NOT having speakers (Dell U3014).  If the link is lost between the PC and the monitor, for whatever reason, Win10 will re-enable this device and put my audio on that as the default device.  So ridiculous.
 
Windows 7 never screwed with the sample rate...ever...even when flipping back and forth between Windows sounds (e.g. Media Player, VLC, iTunes), Firefox sounds (e.g. YouTube), and other applications running ASIO (e.g. SoundForge).

I have a Firewire interface (MOTU 896Mk3 Hybrid) and do not have any problems with the MOTU, PC audio or losing audio.  I have mine set to 44.1Khz.  I don't use 48Khz as I don't do any audio for video.  I have the Win 10 Fall Creators Upgrade installed (also worked OK before the Fall Creators Upgrade).

fireberd
I have a Firewire interface (MOTU 896Mk3 Hybrid) and do not have any problems with the MOTU, PC audio or losing audio.  I have mine set to 44.1Khz.  I don't use 48Khz as I don't do any audio for video.  I have the Win 10 Fall Creators Upgrade installed (also worked OK before the Fall Creators Upgrade).

With 44.1kHz, then you're already good friends with Windows 10.  It won't try to change your ways because you're already where it wants you to be.

2:43AM
 
I guarantee that when your audio is lost, and there is no sound, you will find your PLAYBACK DEVICES set to 44100Hz.  Usually you can set it back to 48000Hz (or whatever rate you're using) and get the sound back without delay.  However, sometimes it completely borks, and your options will be unavailable.  It's locked up and the PC will require a restart.
 
This is one of the biggest annoyances I have with Windows 10 for audio-related stuff.

Yup, same with me when I try to set my audio at 48KHz.  Windows likes to play with me.
 
If I set everything at 44.1KHz and leave it alone, everything is happy, and coexists.