Thanks for this, it made me triple check. I had the right output set for pass through but not the main audio out.
Thanks for the help!
You should describe your setup (connections, signal chain etc) in detail and post your FULL Kodi audio settings.The Kodi audio settings are not particularly intuitive and most likely you simply have a wrong setting.
AAC passthrough is not supported any more so with AAC soundtracks Kodi must decode first, then you have a choice between output the PCM or convert to AC3.