I have only one question.  Can it be used forever? Because our brain ans neurotrasmissors/hormones usualy regulate their activity and dossge by how much you alrrady have of a funciont operation. If some brain function is down, the regulation tends to increase the dosage of.substances in the blood that help the process into going to the new normal. If the same function is babove the normal rate for too much time the brain will stop the productions of substabces and even block some synapses to the stimilus. The result is atrophy a hormonal system. If, for example, i inject, constantly, a hormone into the blood flow, the brain will stop its production by itself. This is a form of dependance. 
So, about sleep. I supose this works like a small soporific. Could it be that the constant use make one unnable to fall asleep alone, if he wishes to?
Thats the reason why soporifics dont cure insomnia, because the are paliatives, often prescribed in emergencies or more serious cases where the doctor need the patinte to recover the sleep soon. Insomnia can only be overcomed by your learning and self control, by therapy (it depends on your case, the doctors will always do what they think its best).

Resume: can one use ASMR/binaural beats forever without negative effects on his own sleep metabolism/physiology ?

Obs: follow your dr prescription, if he get you sleep medications, use it. But never use it by yourself, opinion or judgmente before going to a physiciam.
Hey, sorry I missed this post originally!
Binaural beats aren't chemicals, so your body can't create a dependency. I used to have excruciating trouble getting to sleep but now I don't. I'm certain that years of using binaural beats helped with this -- it got me into the habit of "actually getting to sleep at night" until one day, when I no longer needed them.
I hope this helps!
Paulo Amaral