@Startingover, How do you change your filter?
If you look on the right side, there was a leak and you can see the trail of dried water.
Around the cut out on the left side, where the copper line and the wrapped line comes out, there is quite a bit of mold growing. That is also where the condensate line is coming out. It is probably the copper line, but it seems small. Can you see around the backside?
When was the last time it was serviced?
You should have it serviced soon. When they come to service it, have them make sure that the drain line is open and that it can cleaned by you regularly. And that it is of sufficient size. And that the catch basin isn't rusted out.