All travel CPAP devices create a different/louder sound than a home CPAP. The reason for this is the motor and fan must work harder and spin faster to create the necessary treatment pressure.
Two options to help resolve this issue are:
1) Use a 6-ft. hose instead of our 4-ft hose.
2) Add a Q-tube or Q-Lite (acts as a muffler and helps to mitigate the noise that is radiated to the patient down the hose).