This has been happening a long time and I originally thought it was my mouse (with the camera problems) but I've tried a different mouse and it still happens.

Basically I'll be in a fight in a dungeon for instance, and then the camera will get laggy and move jagged, as I turn the mouse. Sometimes the camera gets stuck facing in one direction, no matter where I move the mouse. Its usually only for a few seconds but is very annoying. When this happens it also causes my camera to spin 180 very quickly and I'll end up facing the wrong direction. Its very easy to get lost when this happens as well since it turns my sense of direction around, also very annoying.

It seems to happen gradually, like the longer the game has been running. I have tried unplugging my mouse, and even tested another one when it was happening, and it still occurs.

Also around this time my character can get stuck running in one direction, despite me not pressing the W key.

I have no idea if there's a setting I need to change in game or if there's something going on with my computer at these times. I've tabbed out and checked everything was running fine, no weird processes etc. I have tried playing with the smoothing option on as well in camera settings. And the mouse settings in windows with and without the enhance pointer precision option.
Any mouse options/camera options in the game are default, except for FOV.

Using Windows 7, 64 bit.
Graphics: AMD Radeon HD 6670
8GB Ram
Processor: AMD Athlon II X2 250 3.00 GHz

Hoping there's an easy fix for this that I can do, its not a severe issue, I've played the game this far with it, its just an annoyance, and if anyone might know what this is, I'd really appreciate the information!