Guitar and microphone get plugged into different channels on the CC1. Keep all of the volume controls all the way down. Plug a speaker cable from one of the Speaker Out jacks to the speaker cabinet. Turn on the CC1. There should be no sound coming from the speaker, other than perhaps some hiss. Turn the master volume up about half way. Still no sound, but there might be more hiss. Then slowly turn up the microphone volume, while speaking into the mic. You should now be able to hear your voice coming from the speaker. Then, do the same with the guitar input.