Please note:
         This product applies the latest power technology. Therefore the working temperature has dropped significantly compared to the previous generation products. This allows leaving power on over the long term.
        This product is burned-in for at least 300 hours before shipping.
        We recommend burning it for an additional 300 hours for best results.
        The quickest way to complete the burn-in of this product is to play music continuously.
        Do not immediately power on the unit after powering it off. Wait for at least 30 seconds.

Normal working state display:

Digit on top:
         Input signal sampling rate indicator; 44.1, 48.0,88.2, 96.0, 176, 192, 352 and 384 are for the PCM formats, while 064, 128, 256 and 512 are for the DSD formats.
Leftmost digit on bottom:
         Output channel indicator, H mean for headphone output , P mean for preamp output ,D mean for DAC output.
2nd digit on bottom:
         Gain indicator. H mean high gain 26DB, L mean low gain 13DB. (High gain design not recommend connect the in-ear headphone.)
4th digit on bottom:
          Input channel indicator, either 1,2,3,4,5 .
5th digit on bottom:
          Volume control number , from 00 to 99 range.

Button functions：
Left button: (Only available while user want to change the set  feature .)
        Push the left button once, the leftmost digit of bottom will blink, which indicates it is selected. This allows changing the corresponding setting. Push the right button to select the desired value. While the display is still blinking, push left button again , the next digit to the right will be selected and blink.
         While the rightmost digit of bottom is blinking, push the left button one time, the menu will change to page 2. While the rightmost digit of the page 2 is blinking, push the left button one time, quite the set menu and back to the normal state.

Right button: (Mulriple functions.)
         While the display is in normal state (not blinking), it allows selecting the input source in decreasing order. The digit on top will be displayed:
"IN1",for the HDMI-IIS digital input; (The HDMI-IIS need the source HDMI-IIS output has the same pin definitions for compatible and work. It can't work with the TV or computer standard HDMI output .)
"IN2", for the USB digital input. (For Windows , the computer must install the driver for recognize the device. Mac, Linux, IOS and Android don't need driver install.)
"IN3", for the optical digital input; (For the best sound quality , R-27HE optical input sensitivity rigorous follow the worldwide standard, it may can't work well with some models TV, TV box or game box  optical outputs if weaker than standard.)
"IN4", for the RCA coaxial digital input;
"IN5", for the analog input.
         While the display is blinking, the right button for set the menu value for change the setting.

Knob:
         For change the volume .

Setting state display：
Menu Page 1:


Digit on top:
         When push the setting button,the digit on top show the product inside temperature of celsius .
The leftmost digit on bottom: Output channel select
        H mean for headphone output ,
        P mean for preamp output (with volume control),
        D mean for DAC output (Fixed output level without volume control).

The second digit from the left  on bottom: Gain select.
        H mean high gain 26DB.
        L mean low gain 13DB.

The 3rd and 4th digit on bottom: OS and NOS mode select.
        While working under oversampling (OS) mode, the lower the oversampling level is, the warmer the sound will be. While working under non-oversampling (NOS) mode , the sound even more warmer and smoother. The possible values are:
        N0 : New NOS mode.
        N1 : Classis NOS mode.
        O2 : 2X oversampling
        O4 : 4X oversampling
        O8 : 8X oversampling

The 5th digit on bottom: The DAC and Preamp output select for the rear outputs.
        P : The rear output ports with volume control .
        2 : The rear output ports with 2V RMS DAC output level (XLR).
        3 : The rear output ports with 3V RMS DAC output level (XLR).
        4 : The rear output ports with 4V RMS DAC output level (XLR).
        5 : The rear output ports with 5V RMS DAC output level (XLR).

 Please note:      
         The RCA output has a half output level of the XLR.
         The headphone output always with the volume control.
         The input 5 XLR always has volume control.

Menu Page 2:
The leftmost digit on bottom: Simulates the sound of a turnable
        S (Simulate) : Activate the phono simulation feature, and we recommend to set the DAC on OS2, NOS0 or NOS1 mode for best results.
        d (Disable-Simulate) : Disable the phono simulation.

The 2nd digit on bottom: Display auto-dimming setting
        A (Auto Dark) : Enables the display's auto-dimming; the display will dim 10 seconds after the buttons are left untouched, only keeping a LED bar lit to indicate the unit is turned on. As soon as a button is touched, the display will turn back on.
        b (Bright) :  Disables the display's auto-dimming, the display will remain on at all time.

HDMI definitions : (Apply HDMI transmit the IIS signal, the pin's definitions must exact same )