Problem with BGM and Cutscene

[darcdensetsu]

I've tried several games on PPSSPP 0.7.6 Windows Version, overall the game play smoothly. But it seems i can't see any cutscene and background music ( BGM ) won't play ( although SFX play just fine ). This is list of game that i've been playing so far :
- 7th Dragon 2020 II
- Black Rock Shooter
- Blade Dancer
- Brave Story : New Journey
- Dragoneer's Aria
- Fate Extra
- Hexyz Force
- Ragnarok Tactics ( some text don't show )
- Y's Seven

For reference, my system is :
- Windows 8 64 bit
- Intel Core i3-2328M 2,2Ghz
- DDR 3 6 GB
- Nvidia Gefprce GTX630M

How can I solve this problem ?, or it's not posible right now ?
thank you before.