There is a service for this, the dealer or an independent mechanic can do this.
Cause is usually a blocked or partially blocked condensate drain under the car. If you get the system cleaned out and the drain cleared I would at that time also get the cabin filter changed out.
Yes, the sprays work. Doesn’t have to be a special brand. Lysol, Seventh Generation Disinfectant, or Meguiar’s Air-Refresher will all work. It is more where you spray. Definitely change the cabin filter and spray inside the compartment before installing the new filter. Then while running outside air circulation, spray liberally into the left and right air intakes of the cowl under the hood (honeycomb grid below windshield). It will suck it right in. Turn the blower to high. Do it for both AC and heat. Lastly, spray liberally into the interior air intake under the glove box running inside recirculation on high. Important: Open your windows while doing this and avoid directly inhaling the air from the vents.Is there a volvo service for this? Will the sprays work where you spray in the duct with those special cleaners with tubes attached to them?