Audio mixer 4 channel stereo

This is a simple audio mixer for mixing up to 4 stereo channels. It lets you adjust the level of each channel separately, as well as the final output level, with a simple 4-LED level indicator on the output. Each input can be switched between stereo and mono. The mixer is powered via a USB-C connector, and the audio inputs and output use 6.3mm stereo jacks. Use it to mix audio from multiple receivers, combine mic and PC output, run several TRX in the hamshack together, or mix musical instruments.