In fact E-AC3 is also commonly called AC3+ and FendiMan is refering to this possibility:
https://forums.openp...ac3-in-openpli/
So he is asking for an option to turn AC3+ into AC3 (and not into PCM Stereo) so I guess that this should be foreseen by the manufacturer driver but it's not so not sure that OpenPLi can do anything about it.