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Controls the device power.
Shows device status, input, format, rate, and volume.
Features 6.35mm single-ended and 4.4mm balanced headphone outputs.
Used for menu navigation and volume adjustment.
The OLED screen displays working status and functions.
Select input ports by short-pressing the knob.
Adjust volume via knob; includes fixed output mode.
Enter/exit menus, switch items, and adjust options using the knob.