I agree with Prism. I'd put in a high quality monofilament in the bobbin (wind very slowly & only fill about half full) and call it a day.
That said, I've never actually had to do that. I use Aurifil in the top & bobbin. Usually, I match the colors, but I have used different colors top/bobbin with a 50wt/2ply and have never had any issues with it not looping in my batting. What kind of batting are you using? If possible, maybe you could try a thicker batting. I use W&N or W&P 100% cotton battings.