trackpoint was not working effectively, not responsive to light pressure, was working in all directions though
purchased new tips to replace thinking this may be the problem
old cap came off very easily, however there was plastic bits? inside old cap which appeared to have a square 'hole' which located on the TP shaft?
looking at post in keyboard it is just a square vertical shaft, caps are very 'loose' on shaft and obviously not 'right' as it no longer works! im assuming that i either need a new plastic insert that goes into the cap (hinges)?? to fit between the shaft and helps locate the red rubber cap? or is the complete trackpoint unit need replacing?

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