Hi KillerWhale.
It seems your question was met by silence. It is, however, a problem I have experienced in the past and (maybe luckily) have not experienced for a while.
I used to just wrap the bait cotton around my bait and then break it off. Understandably, then the cotton would start to unwrap in the water, and not long after that, start wrapping itself around my sinker trace. More recently, I have started tying the cotton off onto my bait using two or three half hitches. This seems to have solved the problem.
You can see Rudolph Scheepers and Jerome Charles doing this in these two videos on Saltwater Fishing South Africa:
https://www.youtube.com/watch?v=Dumia1sW910https://www.youtube.com/watch?v=gWT7ypuAC0gWhere I seem to differ from them is that I do three of these half hitches instead of one and that I do my hitches around my bait and not around the hook.
Give it a try, it works for me.
Frans