cant here sound at lock on , need help.

i have a problem with sound in the game lock on , each time i load a mission at some point of the loading the sound stops and doesnt continue later at the mission.
i can here the sound there is at the menus of the game but not at the missions.

i thought the prob is at my s. card becuase it was sound card on my motherboard , but today i bought a sound blaster card 4.1 digital and install the game and the same problem was on .
can some1 please help me .

i upgraded from 1.00 to 1.01 and then to 1.02 through ubi web site but didnt solve it.
p.s

this problem happend to me only at this game so its not a hardware prob

what game is this? is it 'lock on' because ive never heared of that

yes , the name of the game is lockon its a flight simulation.