The Analog Output Select Switch sets the wiring of the analog output. The OUT 1 & 2 positions are for connecting to a smartphone’s TRRS headset input. The Headphone/Line output is for connecting the receiver to a camera, mixer or headphones.
Connecting to a mobile device with the analog audio output
If your mobile device does not accept digital audio input, the Go Mic Mobile Receiver (GMM) can be connected using the 3.5mm analog output. When connecting to a smartphone, you will need to set the Analog Output Select Switch switch to either the Out 1 or Out 2 position.
For most smartphones the Out 1 (CTIA / AHJ) position is the appropriate setting. If your mobile device uses OMTP wiring for the input, use the Out 2 position.
Connecting to a DSLR, cinema camera, or mixer
When connecting the GMM to a DSLR camera, cinema camera or mixer, use the included 3.5mm analog audio output. Set the Output Selector switch to the Line/Headphone setting.
Smartphone Headset Wiring
There are two common wiring standards for smartphone four conductor headset jacks. The CTIA / AHJ standard has the microphone wiring on the final ring, with the signalling (or ground) connector on the second ring. CTIA / AHJ headset wiring is used on Apple phones sold outside of China, HTC, LG, Blackberry, latest Nokia (including 1st gen Lumia as well as later models), latest Samsung, Jolla, Sony (Dualshock 4), Microsoft (including Surface and Xbox One controller with chat adapter), most Android phones.
CTIA / AHJ headset connector wiring
The second wiring standard is the OMTP standard. It has the signalling connector (ground) on the final ring, with the microphone connector on the second ring (which is the reverses of the CTIA / AHJ wiring). OMTP wiring is used on Old Nokia (and also Lumia starting from the 2nd gen), old Samsung (2012 Chromebooks), old Sony Ericsson (2010 and 2011 Xperias), Sony (PlayStation Vita), OnePlus One, and all phones sold in China after 2009.
OMTP headset connector wiring
Connecting the GMM to a headset an OMTP headset input with the Analog Output Switch set to the OUT 1 position, or to a CTIA / AHJ headset input with the Analog Output Switch set to the OUT 2 position, will result in the audio-out being inaudible or very quiet. If you notice that this is the case, set the Analog Output Switch to the other OUT position.