Also tested with CD1 of Harry Potter and the Sorcerer's Stone (DIV3 - AC3 48000Hz - 5 Ch.) and result is the same: AC3filter again shown in build 501 and not in build 803. Build 803 only shows Default DirectSound Device (=quartz.dll)
Avicodec render details are as shown below
(Edited/Correction: Of course these are GSpot render details and not Avicodec! Thanks adicoto)