L.L.
We also tried the baby whisper and found that a few of the tips worked but used all together it was to much for her. I know some parents might cringe on this idea but we left the tv on really low when she was asleep. I noticed when it wasn't on she took really short naps. We tried the white noise but that didn't help. I was worried that the tv would become a issue as she got older but it hasn't at all. Somewhere around the year mark we stopped having it on and it was fine. She sleeps great without it and there was no transition of it not being on.
Hope you find something that works. But I would not worry to much since he sleeps through the night.