I just had the same problem. The epub was fine in ADE, but when I added it to calibre all the quotes changed to the a with a caret on top. I found the thread linked below and tried converting epub to epub with this:
On Conversion Screen: Look and Feel: Character encoding: try cp1252
https://www.mobileread.com/forums/sho...d.php?t=139753
It worked!! Now it looks the same in calibre and ADE.