Firewire death?

As far as X2 goes, making sure that ASIO is selected as the Driver Mode on the Playback and Recording tab of the preferences is the only X2 setting I can think of that would cause problems like this if set incorrectly.  As you said, since these problems occur with regular windows playback, it is probably not an X2 issue.  

What version of Saffire MixControl are you using?

Have you optimized Windows' settings for audio performance?  Here is an article outlining this:


http://www.focusrite.com/...en/article.php?id=1071


Have you checked your DPC latency?  Here is a tool: http://www.thesycon.de/deu/latency_check.shtml

Run the latency checker while playing back audio.  If you see any yellow or red bars, there are DPC issues going on.  


If you still having trouble please contact Focusrite tech support via this link:


http://us.focusrite.com/contact-support

I suggest that you use Saffire MixControl 3.1 as I doubt that MixControl is the problem here.  To confirm, disable the Pro  24 in device manager and check the DPC latency again.  If you still have spikes, it has nothing to do with MixControl.

LatencyMon is a great for the fact that it shows the highest source of latency.  This will help you greatly in hunting down the offending devices.  I like to use both programs; I find that the visual representation in DPC latency checker is more intuitive.

DPC latency can be a pain to sort out, but the good news is that it usually can be resolved.

Saffire MixControl 3.1 supports Windows 8.

My son bought a $1.500 Dell Laptop and in the end he could not get rid of the DPC spikes. If anyone could have figured it out it would have been him. He even partitioned his drive and installed Linex, Then even OSX. Audio would just not work. His conclusion-  With Laptops sometimes it's just embedded in the BIOS. Bad combo of components. He bought a $500 Acer that works perfectly. 

Seems like mf01000.sys is a culprit. What is it? If it is a low-level network driver, then tcpip.sys and ndis.sys would be victims, not causes. One possibility could be your network cable -- is it securely connected at both ends? When you kill your networking, are you doing it at the bios level, i.e. disabling your network card? A few network interfaces behave badly when cables are not connected and when they first connect.

It looks as if you're running an Intel machine. 2 culprits for high DPCs can be found in the BIOS. Check and see if Speedstep is enabled, it will probably appear as CPUEIST in the BIOS. Also, disable HPET in the BIOS, it's not as bad for DPCs but it should bring them down by turning it off.

Phew! I see DPC Latency and Latency Monitor charts in my sleep, surrounded by an audio field of clicks, pops and momentary dropouts. The end result of doing this and doing that resulted in wasted motion, for the most part. For some reason, the culprit of the clicks and pops had eluded me. It was Malwarebytes. I disabled it and all noise went away, and DPC showed nothing but green. The second problem was the momentary dropouts. During my investigation, I had removed the firewire device, Saffire Pro 24 and replaced it with a dusty, ancient USB Line 6 device. Unfortunately, the problems continued, so I went back to the Pro 24, having ruled it, and firewire out as the culprit. So, what was causing the momentary dropouts? While in X2, I decided to shut down the three plugins I had working. They were Sonitus EQ, Sonitus Compressor and Elephant Limiter. When I opened Elephant's settings box, I saw the word DEMO and hovered over it with the mouse. In bright red text it reported , "dude, this demo will drop out audio every 45 seconds"..... I also just verified the severe distortion in Youtube videos is gone. Thanks so much for the interesting time, MalwareBytes.