There are two ways to route the audio output from NextD Player to your home theater's sound system.
1) Digital audio through HDMI
1.1 Connect the NextD Player to an HDTV or AV receiver directly through an HDMI cable.
1.2 Connect the HDTV or AV receiver to your home theater's sound system through a matching audio output/input port.
1.3 If you use a projector as display for NextD, you may want to connect the NextD to your sound system's HDMI input port first then connect the sound system's HDMI output port (or HDMI ARC port) to the projector.
1.4 The HDMI option is recommended for maximally preserving the digital sound quality.
2) [NextD N2 Only] Digital audio through SPDIF
2.1 Connect the NextD Player to a sound system using a 3.5mm digital coaxial SPDIF cable (looks similar to RCA cable but not the same)
2.2 Adjust the Settings on NextD N2 so that the Digital Sound is set to SPDIF from the default PCM
3) [NextD N1 Only] Analog audio through the L/R (white/red) audio ports
3.1 Connect the NextD Player to your sound system directly using an RCA cable's RED (R) and WHITE (L) analog audio lines.
3.2 If you choose this option, make sure to check the system settings on NextD Player by going into Settings->Sound->Audio Output Mode and check both AUDIO_CODEC.
3.3 If you don't plan to output sound via HDMI, you can uncheck AUDIO_HDMI, but we recommend leaving it checked so that your TV receive audio signals as well. You can simply mute the volume on TV so that it doesn't compete with the audio from your sound system.