Device Priority not saving (V1.0.3.96_2.0.59)

Hello,

I am trying to use QOS for device prioritization, when I hit "apply" the changes I make do not stick. For example, for my desktop, i want it to be the highest priotity as I do all my gaming on it. Below are the things I have tried so far

Factory reset

Rolling back to previous firmware

Using different browers. 

None of the above has worked. I just bought this router a couple of days ago and would like to make use of it's features.