When either adding or editing a "Play a Sound" action, if the "Channel" selection is changed, and a new file is selected after this, the "Channel" dropdown reverts to the value it had when the window opened.
E.G.
- Add a "Play a Sound" action to a command
- Change the "Channel" value via the dropdown to something other than "Default"
- Use the "..." button and add a sound
- Note that the "Channel" value has reverted to "Default"
As an aside, the "Channel" value for a new "Play a Sound" action is always "Default", whereas other such controls often remember the last-saved value. This could be by design, just making note of it.