Press to select between USB, Digital Inputs 1 and 2, and Bluetooth. The corresponding LED will light up to show which source has been selected.
Digital volume control
Press to select between three different filter modes: Fast, Slow or Short Delay, see later section for details. The corresponding LED will light up to show which filter has been selected.
Incoming sample rate
In the presence of an incoming digital stream, the relevant LED will light up to indicate the incoming digital sampling frequency. MQA has the following variants: Green means MQA, Blue means MQA studio. Magenta indicates that the unit is rendering an MQA stream or file. DSD will light up when native DSD or DoP streams are detected.