Not caclulating "Water to add" correctly after setting water/grain ration

It seems like my mobile app is not calculating the "water to add" correctly on my infusion strike water to the mash after setting  my water/grain ratio.  For example, I have 23 lbs of grain.  I set my dough-in water/grain ration to 0.333.  It is my understanding the water to add should be 1.91 gallons of water to add at dough-in at temperature X.  In the settings for my dough-in step, it does show 1.92 gallons to add but on the edit mash screen, it shows 2.11 gallons.  Then on my protein rest setup, I double the water to grain ratio to 0.666.  This again should tell me to add 1.91 gallons (equaling a total of 3.8 gallons total) of infusion water to add but it is calculating 1.73 gallons.  Am I missing something on my setup?  This seems a bit weird to me.  Is there someone who can give me any insight to this?  My final infusion will be for the sugar rest up to 1.250 water to grain ratio.

Thanks

I'm guessing that the extra water that is being shown when you look at the edit mash screen is because you have a value in the Mash Tun Deadspace Addition field in your mash step. (2.11 - 1.91 = .2 gallons).

That is it!!  Thank you for your help!  Make sense now.