Changing rudder lines

Hey sorry a bit of a rookie here but the lines on my Epic V7 got frayed and I bought some Dyneema braided 2.5mm line to replace them. However after installing it following the instructions from Epic and properly routing it, I noticed that these are not only thinner than the original Epic lines but also way more slippery (they are probably meant for kitesurfing) so it actually slips too easily through all the pedal grommets and causes my rudder to misalign easily. I have tightened the turnbuckle but it doesn't help and the only way I can adjust it back is pretty much grab the entire turnbuckle and move it side to side until the pedals align somewhat. Quite frustrating as it misaligns as soon as there is no pressure on the pedals.

Does anyone else have this problem and did they find a way to resolve it or do I have to find a thicker and less slippery line?

Much appreciated.

I have not heard of that problem. Does not mean it doesn't exist. Have you had somebody else with a lot of experience with skis look at it? Maybe it is something simple you have overlooked? That would be nice.