Thing to do is follow the signal path which is easy to do on the T112. To begin with speak into the mic and look at the channel the mic is plugged into and do the lights indicate that the signal is getting in? If yes then look at the output channel and see if the lights light up when you talk into the mic. If yes then the signal is getting through the desk to the output.So now press OUTPUT on the surface and make sure your speakers are patch to the output sockets of the mixrack. If the signal doesn’t appear at the output you expect it to then you have to check the routing of that signal on the desk, is it routed to a group and that group isn’t routed to the output? Or is there a mute on somewhere you don’t know about? Press select on the mic channel then press Routing on the surface and it will tell you where its going

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