The rotary looks like it has a belt or gear reduction drive, so check for crud / dust / whatever packed into the drive train. Also look for wear: does the belt / gearing have any teeth left?
A too-high axis acceleration value can cause the motor to stall briefly, particularly when combined with a bit of junk in the drive train. If you’re using the same acceleration on the rotary as with the linear Y axis, reduce it by a factor of ten, which will not have much effect on the rotational performance.
You may be able to compensate for too-high acceleration by dramatically reducing the Y axis speed, but that also requires changing the machine settings. Reducing the LightBurn layer speed won’t help, because that will reduce the scanning speed on the X axis.
Unfortunately, xTool has a terrible history when it comes to modifying the firmware configuration settings to improve on their defaults. This lengthy discussion covers some of the problems in a situation like yours:
If keeping the drive train clean & orderly doesn’t help, the next steps will be difficult. Other folks may have suggestions, but xTool firmware seems immune to many of the common solutions.