Definitely your blower motor. Remove it and check for any trash or debris in the fan section.Started my car today on my normal commute to work and noticed a sort of blowing and buzzing sound coming from what sounds like the passenger side compartment area. It sounds like the AC compressor is running, however my AC is not on, and when it does turn on it still runs cold like normal, sound still does not turn off. Any ideas on what the problem could be?