Muffled Sound (hard of hearing)--fixes?

My computer setup is that I watch movies on my TV set directly from the computer. So I have about 25 feet of wire running from the computer to go into RCA sound plugs on the computer. I have to turn the volume up so I can hear voices--and these seem muffled and I have trouble understanding them (the problem when watching movies via cable still occurs but is much less then).

Suggestions? Thanks.

you may want to set the bottom right corner of your television on fire

Turn up the volume on the pc through the little speaker icon in your system tray.
It seems like the volume is low on the pc so you turn up the volume on the tv to compensate, and that leads to distortion because most TVs sound like shit at high volumes.