Humidity problem in basement apartment

by Charmain
(Montreal, Quebec, Canada)

I own a very small one bedroom apartment in a semi basement. My new tenants complain about the humidity even though a dehumidify comes with the apartment (they say it is too loud). They apartment is a bit humid during the summer months since there is a lot of rain in the region (Montreal, Canada).

Should I buy another quieter dehumidifier or should I install an air changer system?