Vero 4K, 2017.06-1, currently running the 10bit test kernel, but I have also tested without it and have gotten the same result (logs)
Multichannel audio files are incorrectly being mapped to 5.1 PCM output. I have a 5.1-capable receiver and first noticed this when listening to some 5.1 FLAC that should’ve been using the rears but wasn’t. I downloaded some test files and noticed that the surround L&R were being mapped to front L&R and LFE was being dropped. I tried all possible options for System > Audio > Output Configuration (Fixed/Optimized/Best match). Audio device is AML-M8AUDIO, HDMI and Number of Channels is 5.1. I have tried playing the same files with Kodi 17.3 on my Mac using HDMI output to my receiver (5.1 PCM as well), and all map channels correctly. I have tried disabling System > Audio > Allow passthrough and the DTS file below is mapped incorrectly, but of course the mapping is correct if I allow the pure DTS to be passed thru & decoded by my receiver (Marantz SR7010).
5.1 channel test files (all will announce which channel they should be playing from):