Extruder run differently with same configuration

Dear All,
Recently, I am working on building a delta printer which has a nozzle associated with two extruders.
It means the machine can allow one nozzle to extrude two different filaments.
The hardware has been installed well, but there are a lot of unexpected errors during configuring the marlin for the machine.
The attachment is the configuration.
The marlin passed the compiling.
the machine does work, but not correctly.
My machine has two same models of extruders.
I configured them by same parameters.
Unfortunately, They works differently when I tested them by Repetier-host.
I sent the command to ask them to extrude 100 mm filament.
the extruder 1 is OK, but extruder 2 always extrude more filament and run faster.
They were configured by same values and parameters. I don't know why they run differently.
I tried to switch the hardware of extruders to check if the extruders are different, but the result shows that the extruders are same.
Can anyone can explain this strange event? Thank you.
The attachment is my configuration.

It's NOT necessary to place this question in all subfroums...

Agreed. Seriously considering deleting my replies, which they obviously aren't even bothering to read.

Sorry, I didn't attempt to bother forum readers.
I just try to efficiently pass this question to the readers who have the solution.
Thank you for your advice.