If a card is not in an internal PC slot properly, then low output would be NO output. I doubt very much if the card is the problem in a physical sense.
And as for removing and inserting internal cards, there is only one real tip. Make sure you are grounded before you touch the card - rubber soles and carpets mean when you touch the board there could be a static discharge - which is in computer terms bad. Before you touch the card make sure you touch the metalwork to balance your potential, then remove the screw holding the card to the chassis, and gently but firmly pull it out, and replace the same way. A few cards have a hook in the PCB at the far end that needs to be removed from a clamp. Low volume usually means an adjustment to a software parameter somewhere.
