Changing the filter might help a small bit for about a week the problem is the small condenser, it probably stinks like old socks .....it's bacteria that's growing in the pipes from turning off the air-con moisture stays in the pipes and it stinks ......you can get loads of stuff to help clean the system out ....the best I found was a long tube the you push down into the vents and spray as you pull the tube out....uts like shaving foam and it kills the bacteria and the smell.
Before turning off your AC you should turn it to hot to dry the moisture and then it won't stink like a bad fanny
Hope this helps as my 207 was stinking and the Subaru has the poverty pack no AC only a hole in the roof.
Solved the stink in the pug