Cueing issue

Sometimes when cueing up a lp, there is seemingly an issue where the stylus doesn't connect fully to the record. Everything is set up correctly, VTF, VTA.......Was wondering if any of you have had a similar issue?
Is the arm lift going low enough for all records? If not the lifter can usually be adjusted with a tiny little allen wrench.
It is. That's all been checked as well. If I just let it go, it'll correct itself in a few seconds. When I lift the curing lever up then down...this seems the best way to correct it.

VPI 3D uni-pivot arm.
It happens to me about once a month.  The stylus will settle onto the vinyl but the sound will be scratchy & distorted.  I'll mutter an epithet, use the cuing lever to lift the arm up an then let the arm go down again.  Never fails to work.
@slaw -- Alphason HR100S.  It's also something that doesn't keep me up nights...
Seems unlikely, but sounds like what might happen if the stylus just happens to catch a speck of dust just right. After a few seconds, or if you lift, its gone. Have you been able to look real close while its doing this? Sounds like might be too brief amount of time...
noromance --  Even though for the life of me I can't see how it could occur, I believe you're on to something.  The problem does seem to happen more often at the lead-in groove. 
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 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.
That's what I thought lewm but he says its working. Just to make sure the test would be to raise and lower it with the arm in the arm rest. It should drop nice and smooth even without the arm. If it sticks at all then lewm nailed it.