The DSD button filters DSD content in the user's Aurender Music Library (My Library) based on the settings of the filter. The default is to filter 64x and 128x DSD files from the rest of the library and display only those files (1). By long pressing the DSD filter button, the user may de-select either 64x or 128x files by pressing the checkmarks next to the text (2). De-selecting both, and selecting the "Non-DSD" option will filter all DSD files from the library, in effect the reverse of the default setting. This may be useful if the DAC connected to the Aurender does not support DSD, although the user still may have files of that type in the library.