Effect of temp on foam head at constant psi

My new keezer, fashioned after Quaffers (thanks buddy) sits in a breezeway between my house and garrage. I have it set at 42°F. This room is unheated and resides below freezing all winter. Right now the Dwyer controller says the beer I just poured is 31.4°. Besides the flavor loss, I think the foam head is deminishing. The pressure at kegs is the same. Anybody else see foam head loss at constant psi while temp drops in this range?

Eisendrath

Never served a beer that cold from my kegerator. But it might have something to do with solubility of CO2 at the lower temp.