I'll start with my specs and settings to give a frame of reference.
CPU: Intel core i5 2500k (not OC'd yet)
MOBO: Asus P8P67 deluxe
RAM: G.skill 12 GB DDR3 1600
GPU: MSI Nvidia GTX480
(I think that's all that's relevant)
Xsplit settings:
Resolution: 960x600 or 1280x800 (before upgrading it worked fine at 960x600, I'd like to do 1280x800)
Frame rate: 20 or 25 or 30 fps (have tried all)
Preset: XSplit default
Quality: 9-10
bitrate: 3000 kbps
Speedtest result:
I chose the San Fransisco server because I believe that's close to where the justin/twitch servers are located, the recommended speedtest server provides:
Dxtory settings: (have tried with the XSplit built-in capture and switched to dxtory in an attempt to fix)
Codec: Dxtory default
Frame rate: matches XSplit
Resolution: have tried matching XSplit and matching desktop
Recording is off so its only acting as a camera for XSplit.
This appears to be the best example of the issue at hand: (ignore the audio/mute was listening to something else)
http://twitch.tv/sylvex/b/296684146
You can skip to 1:00 to see the actual test and from there it seems to work smooth until about 3:25ish where it starts to stutter. This test was done with quality 10, 3000 kbps, XSplit default, 30 fps, 1280x800 with Dxtory matching XSplit settings.
While monitoring my PC's status everything seemed to be fine. CPU use never went above 70-75%, RAM use stayed around 60%. The bitrate was the only odd thing I noticed. For the beginning of the test where it runs smooth, the bitrate sits at between 2000-3100, usually closer to 2800-3000, but when it starts to stutter the bitrate suddenly changes and stays at 2000-2100 and never goes above that.
I cannot figure out why so here I am asking for help.
If you need any additional info please feel free to ask. Any help is greatly appreciated.