Yes, it would help if we know the brand, model and amp rating of the converter.
My prior American Enterprizes 2 stage converter would go into cement mixer mode in the middle of the night. :M The fans were shot.
I replaced it with a Progressive Dynamics converter and there is no noise at all. I really do not know if the fans ever run as there is no noise. It has variable speed fans that change speed as needed and it is 3 stage charging with a desulfate mode.It will kick into boost mode on a genny hook up or when you press the charge wizard button to send it into boost or any other mode.
Not all converters hum or mix cement in the middle of the night, but some do. The PD so far does not hum or make noise for the last 10 years since I installed it. I'm sold on them.
Hope this helps
John