In the end big2small or the Amiko ALi App are just passing the full transport stream to the Android device. The Mini HD and the Apps aren't doing any decode of the MPEG2/4 or the audio. If no audio it is likely the device and/or player that can't handle it or is configured wrong.
I'd guess if using MXPlayer and you have to change anything that the METV audio is somehow a little different. I've found with MX that there are several different settings and combos of settings in different areas that can affect A/V handling. With "difficult" video or audio or protocols sometimes you really got to mess with mix and match settings. I've had a couple oddballs where I had to mostly mess with the video to get audio working, as strange as that sounds.
