Have a look at this video that shows you how to connect a microphone to your CommBox speakers  https://www.youtube.com/watch?v=8KdjSqW1s6U&ab_channel=AddictiveTipsTV. It is best to connect the microphone to your PC or OPS first as you can adjust the EQ and record lessons as well.

 

You can also plug the 3.5mm input straight into a Premium Sound Bar if you have one.