Sound properties like volume, pitch and muting are handled in
`BKE_sound_add_scene_sound()`. This is unnecessary, because in
properties are then set to real values in `SEQ_edit_update_muting()` and
`seq_update_seq_cb()`.
Alternatively, it may be better to remove all other updates leave them
in `BKE_sound_add_scene_sound()`. But I want to add muting per channel,
whhich is easier and probably cleaner to do with function
`SEQ_edit_update_muting()`.
Reviewed By: sergey
Differential Revision: https://developer.blender.org/D14269
3cb3167278