I appreciate your concern regarding your mom's hearing loud noises. In case it is Tinnitus, she needs to see an audiologist. In case it is a hallucination, she needs to see a psychiatrist. For Tinnitus, an alternative treatment is hypnotherapy which I provide as a licensed psychologist, but I am not a psychiatrist and so won't be able to help in case it is a hallucination and she needs medicine for it.
Dr. Lata Sonpal
Also consider her taking an Alzheimer's screening assessment - often hallucinations become part of this.