For Audio codec for everything, really would suggest FFDShow, including for AC3 sound, just seems to work flawlessly compared to all other codecs and has solved some related issues to those you are having, this is just a after thought.
Also run filmerit (link in sig) and see if any filter\codec errors are found, padlock button unlocks to allow repair.
Also run filmerit (link in sig) and see if any filter\codec errors are found, padlock button unlocks to allow repair.
United Kingdom