Hi all. I am new to this. I am using a concentrator at home, set at 3. This keeps my saturation level around 93, which is where my doctor would like it. I also have an Activox POC. Even sitting still, I cannot maintain a saturation rate of 85 while on a setting of 4. My question is: am I ( sadly) someone who cannot use the pulse delivery, or might a different brand of POC be successful.