support Remote choose the 4 way input audio

also can add a swtich to manual control the input audio.

this is assembled board.

Product Specifications:
Volume board dimensions: length 82MM    Wide 51MM    highest point 31MM 
Switch board size: 91MM * 54MM *15MM highest point
Voltage requirements: AC9V-12V  or DC 9V-12V
Pot value: B50K (2 channle)

Features

     The audio signal circuit and control circuit completely isolated without interference
     Dedicated MCU control motor potentiometer input relay is stable and reliable
     Volume control board and discrete input selection panel design for easy installation
     Board voltage regulator circuit voltage range can be AC or DC power supply
     Supporting the learning remote control, leaving seven keys for the buyer to freely develop