Camtasia, new install- Video is Choppy/stutters....+ No volume?

[Entry]

I am taking a video with camtasia studio {I have reinstalled it, on a formatted computer}, brand new,

The new video I have taken saved as the file, and when I view it, it is choppy/stutters. (of a full windows screen).

Is it settings? - some settings I need to tweak?

NOTE- As the video Records, the chopping/stuttering starts.

and I also have No volume.... (I have music playing in the background, on realplayer, which I want.) and this music is NOT taken in.