[BUG] language id not set on audio encoded with Qaac

[Selur]

Hmm,... when I try it, I get:

mkvmerge --ui-language en -o "E:\Output\Input_test_qaac.mkv" --global-tags "E:\Temp\Input_test_qaac_2021-01-09@13_33_33_9410__05.xml" -d 0 --default-track 0:yes --default-duration "0:24000/1001fps" --no-chapters --compression -1:none --forced-track 0:yes --no-audio --no-subtitles "E:\Temp\Input_test_qaac_2021-01-09@13_33_33_9410_04.265" --language 0:it --default-track 0:yes --forced-track 0:no -a 0 --compression -1:none --no-video --no-subtitles --no-chapters "E:\Temp\iId_3_aid_0_lang_it_02.aac"

No clue what's happening on your end without a debug output, can't reproduce the issue with the same and the screenshots here.

Cu Selur