We were having this same issue on the TI3 boat, after the rudder upgrade.
We just did a snorkel video tour of the inside of the hull and traced all the lines. There are big knots and excess line all over the place. The lines could catch on each other, the hull, hatches or anything you cram in there. We are cleaning that up.
You may have done this but, using a mirror, start by checking that all the pulleys are still hung correctly, then look for the crossed lines. Cut off dangling line and tape the knots with teflon tape. Lubricate all mechanical points, including the rudder assembly. It should now be smooth as butter.
You can use the descending rod holder tube as a guide for the lines. Put the up/down lines outside and the tiller lines inside this tube. I think this helps keep them segregated.
Lastly - Check that the knots on the T handles are big enough -our UP line slipped and disappeared into the hull! Not fun!