Strange but "mplex" requires an extension of "lpcm" or else you get the following error:
**ERROR: [mplex] File /tmp/dvd_20240130-160930/dvd.pcm unrecogniseable!
bash: **ERROR:: command not found... But, "dvdauthor" only creates the iso files if <audio format="pcm" lang="en"/> without the "l" on "pcm". However, my LG connected to the TV does report the audio as "PCM" even when I did not change the second "ac3" in dvd.sh. And it has always reported "AC3" when I just took the defaults and then when used Mpeg Audio of Layer II or III, it reported it as just MPEG. According to the web, the difference between PCM and LPCM is:
In a PCM, the amplitude of the analog signal is sampled at uniform intervals. Also, every sample is quantized to the nearest value of digital steps. On the other hand, in Linear pulse-code modulation (LPCM), every sample is quantized uniformly and offers lossless transmission of audio signals
OK, more testing. You can change it to just "pcm" and that will create the
iso. "lpcm" does not work and I have not determined what the "l" stands for. I will experiment using just "pcm" and fix the Manual document.