I came home from vacation (about 2 Weeks) and my Faema e98 Compact A1 kept tripping mysocket (US 110V GCFI) when I tried to switch it on. Working fine before I left for 10 years. I plugged it in to a Non GCFI socket and saw sparks internally on the what looked like the left hand side of the unit.
1) What are Possible Causes for the tripping the GCFI circuit?
2) What damage did I do by plugging it into the Non-GCFI circuit with the resulting sparks?

Any help would be appreciated.
Steve