2.6 has the advantage you can add/replace audio track
Extract audio track:
- drag and drop Source video on audacity
(windows requires audacity FFmpeg import/export library, found on Optional Downloads)
- export audio in required audio format
- load the newly saved video (avidemux 2.5) in avidemux 2.6
- Avidemux menu: Audio: Select Track: Audio Tracks Configuration:
-- Track 1 [v] Enabled [Track ..... ] <- Select in drop down menu ..... Add audio track
-- browse and select the audacity exported audio file.
you could have Avidemux 2.5 and 2.6 installed alongside.