Cueing issue

Oh well if its lead-in then its obvious. The program area of most records is almost perfectly flat but the lead-in area on some records is curved with a bit of a lip. So its possible depending on the angle and your anti-skate for the stylus to touch down in the flat area between the grooves, then "ride the curve" downhill at about the same rate as the lead-in groove, so instead of falling in right away its going along the flat surface a turn or three.  

The only other explanations are dust or a sticky arm. I find it hard to believe slaw has a problem with either of those. He's too good. So it has to be the lead-in lip. I've had the same happen to me, just hardly ever, and I know what it is so no big when it happens.

I have read where VPI is having issues with their record cueing device.  I would contact them as I believe there is a newer and improved version. 

I've had one replacement cueing device already and it wasn't an improvement The issue there was it doesn't have complete/full travel depending on how it's set up.. The fix was to place some sticky dots on top of the arm rest.to make up for the lack of travel.

There is not much downward force on the cueing device, to make it reach the full extent of its travel toward the surface of the LP (=VTF plus some mechanical advantage due to the location of the cueing device near to the pivot).  In this case, the cueing device may just be sticking at some point before it hits the bottom of its travel, on the occasions where you notice.  You might look into ways to lubricate it or maybe replace the damping fluid with something less viscous.  The Alphason is decades old, so maybe new damping fluid is in order.

The cueing device can be repaired....there are instructions on the VPI forum website.  ...also it can be replaced with a new one.