Skoree vsego eto AC3 codec, on seichas populyaren dlya AVI.
Otsyuda skachai virtualdub, vozmi versiyu iz bottom stranizi - VirtualDub s AC3 support. A tak sama procedura ochen prosta - otkril file v VB, viberi - direct processing for audio, v File, viberi save audio as wav. Esli direct processing, to chitai nikakogo encoding, sdelaet tebe AC3 file (process nazivaetsya demultiplexing). Esli viberish encoding, to sohranit v tom formate, kakoi viberesh.