leaky tranny

I have a 97 legacy L AWD with a manual tranny. For the past couple of months it has been slowly dripping tranny fluid, it takes about a month to go from the full to the top up line on the dip stick.
I cant seem to find out where its coming from the pan and drain plug are dry, same with where the axels meet up. Is there anywhere else it could be leaking from? It leaks right onto the exhaust y pipe and smokes, not a big issue but would be nice to fix.

Thanks