We just recently installed a Sherline Rotary Table on our Taig CNC with Xylotex motors and drivers and EMC2 (2.2.2).
The Rotary axis seems to work fine with rapid moves "G00", so simple indexing is not a problem.
We are experiencing very slow rotary table movement during some G01 movements.
The slow rotary table movement occurs approximately 25% - 50% of the time.
It doesn't seem to matter if the "A" command is combined with XYZ (continuous 4-axis) or on a separate line by itself.
I have seen a few posts that try to address this ( and have implemented the "fixes" ), but they haven't worked.
---- s. kiwols