LSL6: Saves may not restore with working music fade-out

[RayKoopa]

• ScummVM 2.6.0git6340-g974c51b4cd1 (Jun 5 2022 09:42:22)
• Game language: English
• Game version: Hi-Res 1.000.000
• Windows 11 21H2 10.0.22000.675

Steps to reproduce (not 100% sure yet):

• Leave a room which causes a 5 second volume fade-out of the previous room's background music before starting the new room's music (for example, when entering the hotel interior from the pool).
• Save the game while the fade is in progress.
• Restore this game.
• Notice that there's a chance of the previous room's music now being stuck at the volume at the time of saving.

In DOSBox, the behavior is different: The fade-out of the previous room's music "restarts" at full volume and full 5 second duration, and then properly starts the current room's music.

I cannot reproduce this every time yet. It may be required to quickly move "one room further" before the fade-out ends (e.g. in the above example, to a 2nd hotel interior) and then quickly save the game. I attached a save game where this happened exactly like that.
I remember this happening quite often when I tested the previous music channel bug on fresh games. I'll update the ticket once I found an easier / safer way to reproduce it.

[RayKoopa]

Note about moving one room further possibly needed