Product informationModel: FA4Product weight: 230gHigh and low gain: low 4DB/high 6DB BScreen size: 2.4 TFTProduct size: 10.6*5.8*1.68CMBattery capacity: 4000M ACharging time: about 4.5H (recommended charger ≥2A)Battery life: high gain about 14 hours / low gain about 16 hoursBalanced output power: low gain about 390MW/high gain about 460Mw Single-ended output power: low gain about 280MW/high gain about 350MWPrecautions for use:1. If the memory card cannot be read directly, please format it on the computer;2. Samsung white card 130MB/s, 64-256G is recommended; capacity greater than or equal to 64GB = exFAT, le than 32GB = FAT32; allocation unit select 64KB;3. For high-speed cards, all memory speeds can be set to ON in the system settings;------------------------------------------General operating instructions1. The left and right sides of FA4 are the menu or music list page turning; the volume up and down is up and down;2. Long pre the back on to cutGo to the main menu + play preview (approximate information will be displayed when playing)3. Long pre the OK on (middle on) to enter the black screen mode; if you need to change the song in the black screen mode, turn it on in the system settings;4. Long pre the power on to reset;------------------------------------------Bluetooth nsmitter operation instructions:e sure the Bluetooth headset is set to pairing mode; and disconnect the headset from the previously connected mobile device;Then go to System Settings--Bluetooth nsmiion--Bluetooth Scan, find the headset, click the headset name, and the connection will be automatically completed;------------------------------------------Bluetooth receiving and de operation instructions:1. FA4 system settings - "Bluetooth nsmiion - "Bluetooth switch to Off2. FA4 returns to the main interface, finds the Bluetooth de, and confirms3. Turn on the Bluetooth search on the mobile phone, pair it after F.AUDIO (BT) appears, and connect it. When the Bluetooth of the mobile phone displays "Connected audio for media", it can be done.4. Find any music on the mobile phone to start playing and you can listen to it from the lunch box------------------------------------------The relay will work once under the following conditions;1. Power on2. Shut down3. Bluetooth code when receiving a signal4. Switch between high and low gain5. When switching between DSD and music6. When switching between different samples7. Restore factory settings;When the hard de relay is working, there will be a "click" sound, which is normal;------------------------------------------What is the highest specification supported by USBDAC?Support exclusive, support dop=up to DSD256, support native=unlimited, mainly depends on the app, currently Haibei only supports DSD512, so we can only support DSD512------------------------------------------ and electronic file manual, demo video link, XMOS third-party driver for PC: https://pan.bu.com/s/17afFdtXFjiGDkWxOH6g9rAExction code: 6666