Tips for getting sound and mouse to work consistently

[my_name_is_not_tom]

Note: this worked on my Lenovo Y510P laptop.
Find the ScummVM folder. For me, C:\Program Files (x86)\Steam\SteamApps\common\Freddi Fish 3\ScummVM_Windows
Open scummvm-freddifish3.ini
Find fullscreen=true, move it to false
For me, this made the game start in windowed mode, which gave me the mouse and sound consistently. From there, you can either maximize the window or go to fullscreen.

Hope this helps.

[Nu7s]

Didn't help in my case but as this is the top google result I'll share mine:
I didn't get any audio out of my headphones that are connected to a DAC (Kiio F7).
I switched to my speakers that are connected in the motherboard audio ports and the sound worked fine.
My DAC is set to a high bitrate, I assume because the games audio is an old format that the DAC doesn't recognize.