Cracks in Trail Renderer?

Good morning, im currently building a 2D- kind of tronlike racer (but different?) anyway, im using a Trail Renderer to draw a moving line behind my main Characters.

The Problem is there are some kind of cubes drawn inside the Trail? it looks like the Line has Cracks and overlaps (especially if i turn around a lot but also if i go straight)

Im going with a Mobile/Particle/Multiply Shader , the min Vertex Distance is 0.01 and i don't know what else to do... id rly like to keep the renderer instead of going with bezier curves BUT it has to look more appealing :/ on the Screenshot its ofc the right one im talking about

Any Suggestions?