Mac Pro Speakers blew something up.....?

[switters]

I was having a problem with my mac pro speakers. When I plugged them into the mac the sound was a bit hushed. I needed to play around with the jack, put it and out of the port, twist it around the port to make it work better. Yesterday I was doing that and I bent the jack. While that was happening, the computer short circuited. I saw a spark coming out of the speaker port and the computer shutdown. Also, the jack/pin of the speakers broke.

I turned it back on and the extenal speakers don't work anymore. The headphones work but speakers don't.

What should I do?
Did I 'blow something up' sort of speak?
How could I fix this?

Thanks...