What year and model is your car?
I would get the clutch inspected and change the trans fluid to synthetic. See if that helps. If you find out you need to rebuild the transmission let me know. I can get you a 1987 924S transmission with only 53k miles on it for about 1/2 the cost it will be to rebuild your current box. Rebuilt will be in the 1K range.
Eric
Eric.Lynch@itt.com