How to change audio on movie file using ffmpegGUI?

[tecnofobe]

Hello.
I have a large mkv movie file (13.1GB - only one i could find) and the dts audio can't be read on my tv.
I have the ffmpegGUI app with which I want to change the audio to something my tv will read,- aac maybe?
Not sure what I need to do. Do I choose Multiplex or Audio or...? Any help appreciated. TIA

[ProWo]

First you have to encode the audiostream from dts to aac or ac3, then remux the source video with the new created audiostream and without the original DTS stream.

[tecnofobe]

[Attachment 77232 - Click to enlarge]
Thanks for the quick reply.
I see two dts audios in the source file info display:-
Stream 0:1, Audio, dts, 6 Channels, 3286 kb/s, fre
Stream 0:2, Audio, dts, 2 Channels, 767 kb/s, fre

If I go to Audio option on Main page, under the Encode category I see Audio Stream option, then going there I have a Select Stream box in which I choose number 1 or 2. All this seems to do is change the dts value in the adjacent 'info' box from 3286kb/s (option 1) to 767kb/s (option 2).
Or do I go to the Multiplex page and deselect the checked audio boxes on the left and then ...?
Thanks for assistance.

[ProWo]

1) load your file
2) click main
3) click encode audio stream
4) select 2 (the dts 2channels)
5) click encoder
6) select ac3 (or aac) and click encode.
7) click multiplex, deselect the two dts streams on the left and click multiplex.
Done.

[tecnofobe]

Thank you, sir! I would have your babies were I able!

[ProWo]

Thank you, sir! I would have your babies were I able!

[johns0]

Usually when you rip your video there is an ac3 track there already.