Yeah - a common problem!
I know the problem well. It exists on all modern lines with a solid mono core.
My "fix" has been to use an Albright knot - it just seems to hold better. Test the knot several times to make sure it doesn't slip by really jerking on it - a few times. Once you have it tied right, it doesn't fail. Next step is to tie a perfection loop. Then, coat the Albright knot with a couple of coats of Aqua-sea, drying in between coats.
Don't be afraid to clean the line and dress it after every trip - I do, and it works wonders.
BobK
I know the problem well. It exists on all modern lines with a solid mono core.
My "fix" has been to use an Albright knot - it just seems to hold better. Test the knot several times to make sure it doesn't slip by really jerking on it - a few times. Once you have it tied right, it doesn't fail. Next step is to tie a perfection loop. Then, coat the Albright knot with a couple of coats of Aqua-sea, drying in between coats.
Don't be afraid to clean the line and dress it after every trip - I do, and it works wonders.
BobK