i have had it since 2003, i use the bipap machine with the setting 0f 15/8 and a oxygen concentrator that is set at 6 liters a minute. recently i have been experinceing gas distention and bloating in my stomach while using it . as soon as i lay down to go to sleep with my nasal pillows on i start feeling bloated and like theres a bunch of gas in my throat that i cant get up. guess im swallowing too much air. iv been using this machine for 7 years. this is the first i started having these symptoms with it. guess i should call apria in the morning to come take a look at it. anyone else have the bloating feeling.