This question has been about 14 years in the making. I finally remembered this experience...
Once upon a time, while playing the local SF2 machine, I heard two sounds that I never heard since. At least one (if not both) happened on Blanka's stage. One of them was the sound of glass breaking. I don't mean the sounds you hear on the car bonus stage, or any other crashing sounds in the game. This was unique, with the "bong" and tinkling you hear when a large piece of glass is shattered.
The second sound was a woman's scream. A shriek, to be more precise. It was short, but fairly piercing.
To short circuit the possible "owner's manual troubleshooting" type responses ("Is the unit plugged in?"), I'll give some additional info:
1. My cousin and I both heard these sounds.
2. We were both extremely familiar with SF2, playing it complusively.
3. There were no other machines nearby that could have been mistakenly heard.
4. These sounds DEFINITELY came from the SF2 machine (the store was not being robbed, etc.)
5. This was an original SF2 machine. "Accelerator" machines started showing up quite awhile later.
I never managed to figure out what triggered those sounds. They were undoubtedly samples.
We always figured one that some day we would have an opportunity to get our own SF2 board and fiddle around with it, trying to replicate the event. It never happened, and I forgot about it until now.
Anyone have any insights?