Have the cabin air filter changed.
The musty smell coming from your vents could be caused by mold or mildew growth in the HVAC system. It is important to have a professional inspect and clean the system to address the issue.
There may be something blocking the deflectors from sending air up there.
change the cabin filters
Depends on the smell. What does it smell like?
heater core
Perhaps a dead mouse.
you need a new heater core
Most of the time it is caused by a hole in the heater core, do you smell a sweet smell? The sweet smell would be the antifreeze.
Your house may smell like electrical fire or nail polish remover is coming out of the AC vents because you have fried wiring. You should make sure that you do not have a wall fire.
The musty smell coming from your AC vents could be caused by mold or mildew growth in the system. This can occur due to moisture buildup in the ducts or filters. Regular cleaning and maintenance of your AC system can help prevent this issue.
sounds like your air conditioner compressor is bad.
bad heater core bad heater core