Receivers and Audio Components

I just purchased a 5.1 Samsung blueray Home Theater in a box.

This was to replace a previous 5.1. The system sounds great.. I love it. Only surprise is that it came with a passive subwoofer. not too bad, but I prefer my powered subwoofer that I have.

Can I damage my receiver by connecting a power sub to it?

My receiver was working fine until today.I turned it on and I have to turn the volume all the way up to just barely hear anything.I havew it hooked up to a pair of cerwin vega VS-80s.I tried another pair of speakers and got the same thing.Now, I am using cheaper speaker wire,if that would make a difference or not.Like I said it was working fine and then this started.Any suggestions

Sorry for opening a new thread, but considering how old the other ones are, i thought this to be the best course. 

Anyways, I bought a new fuse and bought the new capacitor (1000uf/10v) but i did not pay attention when i took the old cap out, now I do not know which way to put the new cap in.

any help will be appreciated!