Lift up the leather gator around the gear lever (it unclips complete with a surround in the centre console) and then lift the rubber gator bellow... then wiggle the gear stick in its range that currently seems sloppy... If you can see the pin in the gear lever, wobbling in the rod that its going through (rod that goes all the way back to the transmission) then you are suffering from a worn out/erroded gear lever or the linkage rod is worn out, or both...
To check to see if its just the gear lever thats worn out, remove the retaining clip on the end of the pin, and slide the gear linkage rod off of it.. The pin should be straight pin, which should be the same width for all of its length, except for a groove where the clip sits... if it seems scored, or worn into a barrel shape, you need a new lever.
If it seems perfect, and its width even measures as 10.0mm at every point along its length (apart from the clip groove) then its probably the linkage rod which is worn out.
The reason these wear out is because they are made from a plated mild steel... which due to their location, are exposed to damp.. the plating wears off very quickly, then a cycle of corroding, followed by the corrosion being rubbed/worn off through use begins, in other words slow erroding of the pin.
If its the lever thats worn out, we do an exchange service on the levers, with a modified design where the lever pin is made from Stainless steel rather than mild steel... so putting an end to the wear and errosion cycle which kills the standard levers. The alternative is to buy one from Porsche, which will wear out again because its made of mild steel and due to damp will cycle through corrosion which will make it wear out quickly.
If its the linkage rod thats worn, then what you really need to do is either buy a new linkage rod, which is a pain to remove, or you drill/ream out the bore of the hole for the pin from its worn dimension to 12mm, then install some oil impregnated self lubricating metalic bushes, which we also sell as a kit, but could be brought else where.
If neither of these parts is worn out... then your problem is almost certainly with the rear linkage on the transmission... your choice there is either replacement with a Porsche part, or for similar money, replacement with a quickshift, or fastroad shift, like the two that we sell, or are sold by other companies like type911 etc..