I don't have any ideas as to what could cause that.
So maybe I'm not understanding...
In order for 'snap back' I have to presume you are starting recording in the middle of the project somewhere or else to snap back you would have to lose audio.
Are you using punch or manually starting the recording?
You can turn the snap feature off with the N key or by clicking the snap icon in the control bar, but I presume you are not touching the clip when it is snapping. You are only hitting the stop button or space-bar.
Basically, I'm asking for more details.