I have my DSR115 series Yamaha the first obstacle is that the circuit for digital audio can not be activated, as a result I immediately use the cable jumper not to use the digital audio, after that I have used it successfully but for the circuit on the power amp it doesn't sound like this series is in a mute position, can I have baypass to not use mute again, here is the scheme. I hope this group can help me. thanksDSR115.pdf.pdf