[fritsch]

1.) Dependend on setting Optimized or Best Match kodi won't change anything. Reason: If you are in the menues and outputting 2 channel 44.1 khz to the AVR, nothing will change neither if you change the speaker number nor something else. It will change for Fixed (e.g. 2.0 to 5.1, but also only in the case you are not currently on 5.1 which was set by optmized), also toggeling stereo mix up will change the output, but also only if it was not change by Optimized before. Why does Optimized exist? If you think of LiveTV, you watch a movie which is 5.1 and then it switches to commercials, but commercials are only 2.0 - this will reconfigure audio, some samples are lost, you could hear it, that's why the Optimized keeps a "more is better" policy, if it eg. changes from 2.0 midstream or after audio change in music playllist to 5.1, it will stay there to give the user a seamless experience. For Best-Match it will change for every input change to the best matching input. So if you change from a 5.1 flac title to a 2.0 stereo title, it will change - while it would stay on 5.1 (with SL,SR,FC,FL reciving zeros).

2.) I linked the pdf somewhere and can see there enough "bandwidth" possibilities to get dts-hd, truehd working. Also similar chipsets running Linux with amlogic do work, right? DTS-HRA is a nice example for this: As it is transmitted via 2 channels and 192 khz (one does not talk about channels really in bitstream passthrough, it's rather a bandwidth thing: 2 * 16 bit * 192 khz == bandwidth needed to transfer DTS-HD-HR, for DTS you might need: 2 * 16 bit * 48 khz and so on, EAC3 192 khz again for the 7.1 version). Limitation here: 8 channel IEC format support, which e.g. the shield has. Btw. I sent the spec and the request for 8 channel IEC to my Android Audio contact. As I pinged him twice already I don't really feel to ping him again :-). But - hey - if you read this here: How about the 8 channel IEC change?

3.) I think I have fixed that in the nightlies, while reducing the 32 bit format to 16 bit. Could you retry a v19 nightly build for that?

Best regards

Edit: One minor I have forgotten: Kodi only acts for itself! It creates new AudioTrack Sink and a proper stream for it. IF Android system decides otherwise (e.g. to downmix, resample, whatever, ..) - we have no possibility to change that for PCM output, while passthrough is exclusiv and the system has to care.