Can't quite remember if it was a PC or amiga thing.
I recall seeing a Demo of Simon the sorceror 2 at a friend's house. A friend with an A1200, I can recall where the computer stood but I can't recall him having a PC at that spot in his room. As far as I recall he moved stuff around.
At any rate the Simon 2 demo had speech. HD installed. Could've been what you played, if it was indeed on the Amiga.