Sound urgent

IMPORTANT!!!!

Ok to start it off, i have perfect sound on music files/movie files/and games,

1) Gta Sa - (GrandTheftAuto SanAndreas) : I Have sound when i'm loading the game onto main menu,as soon as i click a saved game or start new game my sound goes completely.

2) Internet Page's (i.e Youtube) i don't have any sound atall weather im cheaking a song/video clip.


I Have tride all sort's i.e for (gta-sa) i have replaced the "eax.dll" witch has been recommended iv'e also tride (Run/dxdiag/Sound/Hardware Acceleration Level) to all 4 points and the loading menu sound goes also, so i put it back to default witch it was on (Full Acceleration) and same problem..just the loading menu sound then in-game sound goes completely again..

For the Internet page's (Youtube) issue's i just don't have a clue,

System Infos : Operating System - Microsoft Windows XP Pro
Processor - Intel (R) Pentium (R) D CPU 2.66GHz ( 2 CPUs)
Memory - 1022 MB RAM
DirectX Version - DirectX 9.0c
Graphics - NVIDIA GeForce 6200
Sound - C-Media Wave Device (( is the only thing i can find that seems to be soundcard))

And now im currently on Run/Dxdiag/Sound/and i just ran Test DirectSound and i got this message [DirectSound test results: Failure at step 19 (User verification of software): HRESULT = 0x00000000 (error code)] I Have no idea what this means exactly

Help/Advice would be more welcome and most greatfull,
E-mail me at ( Mikesyklasher@hotmail.co.uk ) Many thanks in advance.

Configuration: Windows XP
Firefox 3.0.12