AltSound present but not enabled
What it means
The install looks entirely correct and stays silent anyway — no error, just no sound difference.
Why it happens
The AltSound files are extracted correctly, but the switch that actually turns AltSound on is a separate per-ROM VPinMAME setting, not a file — extraction alone doesn't flip it.
How Pincab Toolbox detects it
The altsound folder for this ROM has files, but VPinMAME's own Sound Mode setting for this ROM is still at its default (off).
Automatic repair
Repair, included in the Pincab Toolbox licence, can fix this one for you. Your files are backed up first, and the fix can be undone.
Check your own pincab
Pincab Toolbox is a free Windows scanner for Visual Pinball X and PinUP Popper. It finds and explains problems like this one. No account, no telemetry.
Download for freeCovered: Visual Pinball X (10.x) and PinUP Popper. Not covered: Future Pinball, Pinball FX, Visual Pinball 9 and the other frontends (PinballX, PinballY).