[. . . ] CAUTION: To prevent the risk of electric shock, do not remove cover (or back); no user serviceable parts inside. THE LIGHTNING FLASH with arrow-head symbo is intended to alert the user to the presence of uninsulated "dangerous voltage" within the product's enclosure that may be of sufficient magnitude to constitute a risk of electric shock to persons. Before any transportation, your product must be packed correctly in order to avoid any damage. [. . . ] SERVICING The user should not attempt to service the appliance beyond that described in the operating instructions. All other servicing should be referred to qualified service personnel. POWER-CORD PROTECTION Power-supply cords should be routed so that they are not likely to be walked on or pinched by paying particular attention to cords at plugs, convenience receptacles, and the point where they exit from the appliance. CLEANING The appliance should be cleaned only as recommended by the manufacturer. POWER LINES An outdoor antenna should be located away from power lines. NON-USE PERIODS The power cord of the appliance should be unplugged from the outlet when left unused for a long period of time. OBJECT AND LIQUID ENTRY Care should be taken so that objects do not fall and liquids are not spilled into the enclosure through openings. STANDBY/ON POWER BUTTON Press this button to turn ON your appliance, power is supplied to your unit and it becomes operational, the STANDBY indicator blue lights after few seconds. (The main power switch is located on the back panel and must be ON in order to use STANDBY function). When set to STANDBY the main power is cut-off and the unit is no longer fully operational except for the micro controller. COAXIAL DIGITAL INPUTS 1, 2 AND 3 Press one of those three buttons to choose the digital coaxial input that you want to select (Coax1, Coax2 or Coax3). To connect those digital sources, RCA Cinch cables must be used on coaxial 1, 2, and 3. your digital audio converter MDA-503 accepts all signal up to 384kHz/24Bit. OPTICAL DIGITAL INPUTS 1 AND 2 Press one of those two buttons to choose the digital optical input that you want to select (Opt1 or Opt2)). To connect digital sources to those optical inputs, you must used an optical cable. your digital audio converter MDA-503 accepts all signal up to 384kHz/24Bit. [. . . ] L) If your integrated amplifier or preamplifier has balanced inputs, you have the possibility to connect it on the balanced outputs of your MDA-503 for better quality. DIGITAL INPUTS You can connect your sources on those inputs: Coax1, Coax2, Coax3, Opt1, Opt2 et AES/EBU. POWER CORD /MASTER ON/OFF SWITCH / VOLTAGE SELECTOR Before plugging in the amplifier, its master power switch must be in the OFF position. [. . . ]