The only thing I really see consistently is:
Faulting application name: ffmpeg.exe, version: 0.0.0.0, time stamp: 0x4ee7d185
Faulting module name: unknown, version: 0.0.0.0, time stamp: 0x00000000
Exception code: 0xc0000005
Fault offset: 0x00358ff5
Faulting process id: 0x11dc
Faulting application start time: 0x01cd020f0bf0a714
Faulting application path: C:\Program Files\Serviio\lib\ffmpeg.exe
Faulting module path: unknown
I don't think that would cause it but I'm not sure. I've installed the latest nVidia drivers though just in case. I can't seem to reproduce it; it seems random. So it's hard to tell what could be causing it. I don't think it's a faulty power issue because the monitor power light blinks when there is no video connected (like if you leave the monitor on but the computer off) and it stays solid blue during the issue.
It's also never done it while I'm playing Skyrim so it doesn't seem to be an overheating issue. It seems to only do it in Windows. Mainly when I am on the net. A problem with Firefox perhaps?
I've done scans for viruses etc with no issues.