The issue is that the A axis is moving in degrees per minute, and the X axis is moving in mm/minute, and those are not the same unit.
If you combine a linear move with an angular one, the feed rate for the linear move takes precedence, so you have to calculate a feed rate for that linear move that makes the angular move complete in the correct amount of time.
In this case, the X axis moves are miniscule - 0.03mm, and at 23 mm/minute (0.38mm/sec), a 0.03mm move should be over in 0.078 seconds. In that time, the A axis moves 04.41 degrees.
50.8 mm diameter * PI = ~160mm circumference, so 4.41 degrees is 1.96mm of surface travel. If that happens in 0.078 seconds, it equates to a surface speed of 25mm/sec, which is exactly the rate you specified.
Why the pause is happening I can’t say, but the math works out.