This Aviom A320 16 - Channel Personal Mixer is a great audio tool. But it has a known issue: the knob cover is missing.

To use this Aviom A320 16 - Channel Personal Mixer, first connect it to your audio source. Then you can adjust the sound channels according to your needs. When using it, be careful not to touch the area where the knob cover is missing to avoid potential damage. For maintenance, keep it in a dry and clean place. Wipe it gently with a soft cloth regularly to keep it clean and working well.