Help with hookup

This might be a dumb question but I will ask anyway....
What are you using as an input source? CD player? Streamer? Phono? Make sure you have that input source selected and then do you see the needles on the c2300 moving as you turn up the volume ?
try multiple sources if nothing is working could be your main output tubes possibly 

Also try using output 1 or output 2 and select that output on the front of your c2300