When I save a 16-bit wav file (mine happens to be 8 ch), if I click on the sample type options, and Dithering: Disabled, if I close and open the file again I notice noise in the silence portions of my file where it was identically 0 before.

If I do the same, but select Dithering: Enabled, the silence portions are identically 0.

It seems that the Dithering switch is flipped.