If a patient has Alzheimer’s or dementia, do they tend to make these weird mm sounds?

Every dementia patient is a little different and can get into some odd repetitive behaviors. My Gram used to slap her thighs repeatedly. She wasn't even aware she was doing it over and over.

Sometimes the behavior is a sign of anxiety. Other times, it is kind of like being a stuck record. If you can get the person distracted from the behavior and involved in conversation or another activity, no real problem. If you can't redirect, talk with their doctor.

MY wife did this when she was happy to see me an my family. We all miss her weird sounds of joy. May she rest in peace.
“You can’t have a medical field that’s subjected to having to practice according to patient demand backed up by court orders. That is positively horrible medicine" Caplan said.
Ralph Lorigo doesn't see it that way. The attorney from Buffalo, New York, filed his first of several ivermectin lawsuits in January after being approached by the family of an 80-year-old woman who was in the hospital on a ventilator. His second case was later that month, for a hospitalized 65-year-old woman. 
In both cases, judges ordered hospitals to give the women get ivermectin as their families wanted. Both women survived their hospitalizations. 
Is that why i the covid vaccine being order for patients and then dyeing from it, is that right The American people have the right to have their loved one's take what ever will help save their one and not be told by government bureaucrat to be ordered what to take for their families
Please Don't say comment unless you have lost a love one like my wife of 55 years of marriages one because of these government bureaucrat. I would of done anything to save my poor wife. G-d bless these poor people and may he rest in peace

Unless he's found to be in pain, my sense is the moaning is a type of self-soothing, completely unconscious, and perhaps like a baby/small child will murmur and babble. I do agree with many here that it can be a sign of anxiety, fretting within, out of confusion, frustration, and perhaps fear.

At first I would hear "Oh G - - as sis grabbed stomach. Deflecting seemed to help...if I saw someone out walking a cute doggie, I'd point it out and the "Oh ..." immediately stopped while she made a fuss over the dog or whatever pet was out...she always asked permission first, so that was good. Some days it is the humming of some weird series of notes. I asked what song that was - no answer! It just comes and goes.

My husband would make moaning sounds. Sometimes softly other times very loud. Sometimes it would depend on background noise, if there was a game on the louder and more exciting it was the louder he got. I eventually gave up on putting games on for him to watch.
If I was on the phone talking to a friend he would get louder.
If something was stressing him out he would get louder.
He was non-verbal approximately the last 4 or 5 years give or take a word now and then so his moaning and other noises was the only way he communicated.
As for pain, there are facial expression that you can watch for that will show pain. A grimace, a furrowed brow, will sometimes reflect pain.

When this gentleman is moaning have you tried sitting down with him and talking to him in a quiet voice? Keep the pitch of your voice lower and softer. the type of volume you would use for a conversation with a friend that is sitting next to you. Sit next to him. Look at him. If you are wearing a mask make sure that you enunciate very clearly so that he can understand.

In some cases the moaning is anxiety and that can be treated with medication. I would talk to your supervisor about it.
And inform your supervisor of the verbal abuse if you have not done so already. Depending on the type of abuse you could ask for a different assignment. And if the verbal abuse EVER begins to become physical you must notify your supervisor immediately.

I suggest you call your supervisor and tell her the family needs to be contacted. This humming is anxiety and it does get worse. My Mom was put on a med for this. For her, it was the beginning of the end. The next thing she did was close her eyes. Seemed to be able to respond but eventually would not get out of bed. Then she couldn't swallow. Thats when Hospice was called in. Hospice will keep your client comfortable. His body will shut down. No food or water should be taken in once this happens. It does more harm than good. A nurse will check in on him periodically. An aide to bath him, if needed. If you are kept on, make sure the Nurse realizes that you are a County Aide and may not be able to administer any medication. Usually the family is taught how to do this but your agency may not allow you to do this.

If you are kept on the Hospice Nurse is the one to ask questions. She/he should be available by phone 24/7. You cannot call 911. You need to call the Nurse or the agency she works for in any emergency.
This Nurse should be able to answer any of your questions and concerns.

I am going through that with my Mom. At night she makes the mm sounds and then all night long she hollers "Hey." When you think she finally went to sleep, she hollers again. It is so exhausting. I asked her once who she was saying Hey to, and she said they are over there and pointed to the closet. It seems as if she is somewhere else because I have gone to the other side of the bed right in front of her and it is like she doesn't see me. She does fine during the day. She may holler once or twice but at night it seems to be nonstop some times.

That just might be the part of the brain that's being affected by the dementia. There might not be anything to be done about it, but you do need to determine if they're in pain. You don't want to become complacent about whether they're hurting or not.