[FFmpeg-user] How to extract core DTS / DCA stream from a DTS 96/24 stream without re-encoding

[Onetel]

I have a DVD with a DTS 96/24 stream (Peter Gabriel - Play) but where this has a known authoring error where this stream is very quiet. Other owners have reported the same problem, however some who have audio systems which can only decode the core / legacy DTS stream (equipment too old for DTS 96/24) say that it plays fine, so the problem seems to be specific to the 96/24-enhanced part of the stream.

So I want to extract the core DTS stream to be able to play it properly. Is there a way to get it extracted and have the 96/24-enhanced information discarded, without any re-encoding? In essence I want to give the option “-acodec copy_legacy_only”.