Could it be that your computer is either possessed or having an allergic reaction to some music genre?
 
I cannot for the life of me think of what to have you check.  My brain will keep stewing on this and I will try to think of something better than my idiotic comment at the top of my post.
 
You are sure you are not filling up on the SSD?  Not full, but I am dimly aware of some threshold where they start becoming a bit slower.
 
Perhaps some massive fragmentation issue is present?
 
Dropouts seem to be caused by things like settings, background services/applications, antivirus software, device drivers, disk throughput, lack of available resources, and occasionally hardware.
 
Most of that seems to have been checked, per the numerous threads/responses above.
 
Hang in there - something is causing it, and sooner or later either you or one of us will figure it out.
 
Bob Bone
 

To be specific for Windows 8
Change Power-Savings Settings
Change Advanced Power Settings (Link on the screen)
Scroll to USB Settings and expand
Expand USB Selective Suspend Setting
Setting value should be Disabled.

If its on, try and disable the "Vista only" setting in the audio properties. I'm not in front of my DAW, so I can't tell you what it's exactly called. But I know it's for enabling MMCSS thread priorities. I know you're supposed to be able to leave it on for Win7, but my machine gave me fits (and I have the exact same CPU) whenever I tried recording audio until I turned that off.

You're using ASIO mode and not ASIO4ALL right? 
Sonar 64-bit or 32-bit? 
Sonar X2 or X2A? You should be using X2A. 
In the Octacapture Control Panel, what is your ASIO buffer size set to?  Should be 256 samples or 128 samples. 
In Windows go to Start-Computer-Properties. What is your Windows Experience Index? Might point out a bottleneck. 
 
 
 
 
 

Did you check your ASIO buffer (Preferences | Drivers | ASIO Panel)?  If not, try setting it to a high value like 1024 (which would probably be 8 on the slider).

Tripod
I didn't have these drop outs before...now it just seems to get worse every day.
First they it happened what seems randomly. Then it started happening everytime i played a new track when i already recorded 1 or 2 tracks and now i can't record ONE track anymore without the audio engine quitting on me.
I tried the obvious things already but nothing seems to work.
And you also can't tell me my computer doesn't have enough resources.
Any suggestions? I don't know what to do anymore. I can't record even 20 seconds of music...

Make sure the Octa Capture isn't plugged into a USB3 port.
As was mentioned, check your DPC latency (large spikes well into the yellow/red are virtually guaranteed to cause glitches/dropouts)
Also, benchmark your HDs (to be sure one controller didn't slip into PIO mode)
 

What other drives are you using?
 
You mention an SSD - what's the capacity & what other drives are you using?
 
Just a shot in the dark - have you cleared out your picture cache recently?