http://support.microsoft.com/kb/2970191
 
I'm posting this for reference in case anybody has a problem with win 8.1 and an older firewire 400 audio interface.
 
Windows 8.1 came with an updated 1394 firewire driver that causes some older firewire 400 devices to have drop-outs or not work.
Microsoft released the legacy 1394 driver update to solve this problem (kb2970191).
I have installed it and it completely cured the drop-out problem I had with the FireStudio 26X26.
 

So which devices do you have an how well are they working? Thinks for the info.

Depends on the interface drivers. With the latest version of focusrite mix control for instance you should not be running the legacy drivers (earlier versions you had to). Definately contact the manufacturer to see what they recommend if in doubt/consult the documentation.

kitekrazy1
So which devices do you have an how well are they working? Thinks for the info.

Any older firewire 400 device that is no longer supported by the manufacturer for windows (8.0/8.1).
In my case it is the Presonus FireStudio 26X26.
It works like a champ now with the legacy driver. No audio drop-outs, no crashes.
 
You can always revert back to the newer driver if the legacy doesn't work. It does not get deleted.
Note that the legacy driver only supports firewire 400. It does NOT support firewire 800.
 

mikedocy

kitekrazy1
So which devices do you have an how well are they working? Thinks for the info.

Any older firewire 400 device that is no longer supported by the manufacturer for windows (8.0/8.1).
In my case it is the Presonus FireStudio 26X26.
It works like a champ now with the legacy driver. No audio drop-outs, no crashes.
 
You can always revert back to the newer driver if the legacy doesn't work. It does not get deleted.
Note that the legacy driver only supports firewire 400. It does NOT support firewire 800.
 

 There's a lot of nice FW devices that are now legacy.  I won't buy their gear anymore.  I've read that one person has the M-Audio FW410 running fine in W8.   I will probably never use W8 but at least I know that something like this is a solution and this may be a fix for W10.    

Hmmmm .... I upgraded to Sonar X3 recently to a newer Computer running win8.1  My previous setup was winXP with an M-audio FW410 and Radium 49 keyboard. It doesn't appear that M-audio wishes to  update their drivers for either of these.  Sounds like someone was able to get FW410 working. Would that be using the legacy win7drivers for Firewire and the FW-410 ?