Avenue 6 pad wigs out in 6-button mode but works fine in 2 button mode.
Using Chris Covell's Pad Test (I'm running on an Everdrive v2), I see that *any* non-DPad input results in all of the buttons getting pressed. That is, if you press Select, it lights up Select, Run, I, and II.
This is not how it behaves when running on the Duo.