How to play 5.1 audio direct to speakers I have an audio file recorded in 5.1 surround sound. I'd like to play this from my Android Device. 

The issue I have is the various Android devices I have (tablets/phones) all contain the standard 3.5mm jack, which I think means stereo only! I'm not after a simulated surround sound, I need access to the outputs! Maybe it's possible via the USB?

My exact requirement (if it helps) is to end up with 4 outputs. Front left and Front right as a stereo pair and Back left and Back right as a stereo pair (I don't need the sub channel). However, being able to some how split the signal so each goes it's own speaker is also fine, I can worry about the rest. The focus is how the Android device can provide this signal(s). 

The device I want to connect to is http://www.myxlshop.co.uk/j-s-external-sound-card-with-usb-51.html?id=50345220&amp;gclid=CjwKEAjw1qHABRDU9qaXs4rtiS0SJADNzJis52lt2Cd65VkwFDc-wj4r9nsE6FUmd-g0prtGSYITjRoCz3fw_wcB (note it's USB input). Maybe with the new USB DAC input?
There are many ways you can get the audio out.

Through wire:


Head phone jack - you clearly said it can deliver only two channel audio.
USB - You can use an OTG adapter and plug in a 5 channel USB sound card and get the 5 channel audio out.  
USB Type C may have this support native.


Wireless:


Bluetooth - if the A2DP profile is supported (will be supported from v2.0 onwards) you can stream audio in stereo - again not good enough for you.
Screencast protocols like Miracast or DLNA might support as it can be considered as a HDMI connection over Wi-Fi. These should support 5 channel audio.


Of course for all these you have to have a player which has appropriate codec support (usually AC3).