Minecart has stopped working on all of our farms and super smelters on the realm. 

The minecarts will Consistently come to a complete stop before the curved rail.

The minecarts will also occasionally stop on a solid block with a power rail. Where they should bounce off, they stop moving. 

Both of these happen occasionally,  And happen more often then not. 

To reproduce,  Make a line of powered rails. then a regular rail. then a detector rail. then a curved regular rail. (see attached.)