Like I stated in a previous post you need to check the gas supply, its possibly the internal regulator requires calibration and or repair/replacement.
"4.6.1 Checking Gas Supply Connection/Gas Inlet Filter
(See Fig. 4-6-1-1) The gas inlet filter (2) may be plugged or soiled due to Soiling
unclean gas or gas supply residues. This type of soiling, however, cannot
be detected externally. Heavy soiling is especially noticeable during
higher flow rates and results in the actual gas flow falling short of the
nominal gas flow during active insufflation.
If cleaning the surface of the gas inlet filter does not yield any
improvement, the gas supply connection (1) has to be replaced
completely"
Keep in mind this is for the 40L
