Why are my fridge and freezer not cold enough?

We noticed about two weeks ago that our 3 yr old Samsung Fridge, model rf220nctasr, is not cold enough (both fridge and freezer). Since then, we replaced the evaporator fan and cleaned the condensor coils. No change.

Other observations:

- The condensor fan seems to function adequately. It does sometimes run even if the compressor doesn't (we noticed that once).

- The compressor is really hot to the touch.

- The evaporator fan runs and pushed cold air when the light in the freezer isn't on. Can't confirm if it stops working however.

- The evaporator coils are not evenly frosted.

- We do not hear any clicking noise.

- Self diagnostic returns no error.

Repair person seems to think we should replace the freezer evaporator and filter dryer, but from my research, if the evaporator was defective, there would be an ice build up ?

Thank you!!!