I find I need to have intelligent sound (voices) going on as I start to shut down to sleep. It is easier for me to ignore outside voices than to ignore the thoughts going on in my head. Those thoughts are often just processing sensory stimulation.

Basically, I need one sensory channel to distract me from the other sensory channels. Since the auditory channel can be dominant, filling it with stimulation that I can ignore allows me to get my mind settled. When my insomnia was at its worst, I would listen to vocalists singing in a foreign language. I knew just the basics of the meaning of the lyrics so I was not consciously trying to interpret the words. I could just rest and listen to the music of the vocals.

Now, I can use any non-important speaking or singing to provide the distraction. White noise does not help me. It allows my mind to get started in conscious verbal thought.

For some, having something to repeat or sing in the mind may help. I use Amazing Grace as a 'singing in my mind' distraction.

Hope this helps.

My best to you.