No Sound

I have a HP mod# p6340f, prod# v2527aa-aba. I disconnected my tower, removed the card reader and reconnected the tower. Now I have no sound. By accident I connected the speaker cable to the Digital Audio Out. After I had no sound I found my mistake and then connected to the s/sub. Still no sound. As I connect to s/sub or touch cable end to tower frame there is static sound from speakers.

My monitor is a TV. There is sound when on TV mode.

I would appreciate any suggestions.

Mule

BTW, any suggestions as to where to buy a new sd card reader that will fit in the tower as the original one did?