Have you tried talking to your dentist? Some dentists, not all,
when referred by your physician have been using various types of positioner appliances to help sleep apnea/snoring problems. I have found some patients have been able to eliminate the CPAP use by using the intraoral device.
There are some downsides, yes, but they usually relate more to jaw soreness than anything else. You can get an idea of their use by checking some youtube videos.
tap positioner - YouTube