This is rare, but common enough to answer this question in the FAQs. Usually the filter inside the air separator has come loose and is rattling each time the machine is turned on. The fix is simple. Open the hatch (usually on the back of the air separator ) and look to see if the filter has come unplugged. If it has, the solution is to firmly plug it back in. Check to see if you have fixed the noise by turning your air separator back on. If the noise is gone the problem is solved and nothing is wrong with your air separator. When checking your filter use, you can also preemptively make sure the filter is snugly seated on the intake and it will prevent this problem all together. If the noise still persists beyond normal or appears to be getting worse please give us a call.
*Note: Since the 5L AirSep Visionaire does not require any maintenance and therefore the filter is not accessible from a panel, this does not apply to the AirSep Visionaire 5L Air Separator.