@damian101 I copy the stream of DCA and AC3 streams from a DVD, into mp4a and m4a files, as a last resort, to avoid transcoding. Strawberry can play both of these.
I also compress DSD streams losslessly using WavPack. Strawberry can't play them, compressed or not. But to be fair, its closest GTK alternative Quod Libet, also can't play them. I think the only reliable music library based player for these is MPD. It'll even convert it to DoP if you need it to.
But when the stream is PCM, I just transcode to FLAC. It's lossless anyway, so nothing changes.
If you're not willing to go through the trouble of finding a player that can play TrueHD audio, doesn't it make more sense to transcode to FLAC? Since it's lossless, technically it should be fine. There must be a way to get MPlayer to do this. (It can convert audio to WAV; however by default it downsamples to 2 channels @ 48kHz). FLAC can handle multiple channels, high bit depths, and high sample rates, so long as they're PCM.
It might seem possible to use ffmpeg to transcode the PCM audio, but apparently it only supports one channel configuration for surround, so channels are switched around. Just set the bit depth and sample rate on mplayer, and output to a WAV file.
Here's the command I used for Ola Gjeilo's Piano Improvisations:
mplayer br://[title] -bluray-device [disc mount path] -benchmark -vc null -vo null -aid [audio ID] -chapter [start chapter]-[end chapter] -ao pcm:fast:file=[output path]
You might need to switch things around. Replace the square brackets as needed.
It does the job one chapter and title at a time; if you don't set an end chapter, you'll end up with a file with all the chapters concatenated.
Also, bdinfo will print out the audio IDs on the disc. Some distros have bluray_info instead; I don't know if it does the job.
You'll have to figure out the title and chapter using VLC.
If your Blu-ray is encrypted, you'll have to use MakeMKV. It's not free though. Also, the output is an MKV file, so all commands to extract audio from the MKV file will be different; I haven't figured them out yet. MPlayer is very hard to use...