Stimming

My son in his 40s was diagnosed with level 1 autism 3 years ago after mental health issues all his adult life.  He was made redundant last august and then got sepsis in September which has left him with ongoing painful disabilities.  He now lives with us.   He has always had trouble sleeping and Lately he has started stimming by chanting, singing and this goes on for hours through the night. How can we address this so we can get some sleep?  He doesn't seem to understand how this affects us.