Well, normally this is from a misplace for some reason and the part is bouncing around the PCB, it should have been on some pads somewhere, Do you know if this assembly also had "missing" parts? Could be temp loss of vacuum during xy seek and part fell off nozzle. Or nozzle size too small for part and it falls off during a rotation or Seek.
Another reason is bad paste application or bad paste causing part not to stick when placed.
Judging by your other thread, it seems as though you are having a lot of pick problems with current equipment. feeders may be causing parts to picked up as billboard and then during placement getting "squirted out" due toi increased height.
Should be a start anyway
Russ
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