BattleField Bad Company 2 sound problem

I have weird problem with sounds in BFBC2. When i play i normally use my homecinema for audio, but at night time i have to change to headphones / headset because im living in blockhouse. But there is a problem with my headphones.

Ok, when i turn power to my Nokia-BH604 and listen any sounds in windows or other games they work just fine. As it should be. But when I load BFBC2 (original bought one!)i hear mainmenu sound normally. When i go to serverbrowser and choose server to load up sound disappears in loading screen. Totally quiet.

If I quit back to mainmenu, i have ingame sounds coming with big delay. I hear the sound that i didnt hear ingame.

Sound problem is only in onlinegame, not in campaign mode - there sounds are normal.

I hope you have answers for me, before i burn my computer and headphones.