im usually getting the smell on a cold start.How are you turning the AC off at the end of your drives? The AC pulls moisture from the air and some of it will stay in the system and start smelling funky the next time you use it. Best practice is to flush the system with dry air before turning the car off. About a minute before you turn the car off (home stretch for your drive) turn the AC off and turn off 'recirculate air' so the car is pulling fresh outside air. This will evaporate that residual moisture and hopefully correct the issue. Good luck!