The configuration of pipes on the left site merges two consecutive packages into one and leaving one space between each package.
Setting the left valve to following values has the described effect:
<=500g/s: The packages are merged and one space is left between the next merged package.
>500g/s: The packages are merged and one space is left between the next merged package. The gas that could not be merged due to volume > 1000g stays behind decreasing the flow rate.
Edge case 1000g/s: packages are spaced one apart effectively halving the flow rate.
In the save the valve is set to 309.9g/s and the effect can immediately be observed upon unpausing.
Steps to Reproduce
Construct a pipe section as shown on the picture
This issue has not been confirmed by a developer yet.