Recommend settings for Galaxy Grand i9082. Help needed from the experts :)

[Ammarmsms]

Hi there, new guy here. My friend recommended me an apps called PPSSPP v.0.9.1 he played on his Mini 2 and some how I found it interesting so I might as well check it out. I've downloaded 2 games 2 days ago which is Project Diva Extend and Megaman Maverick Hunter X . I tried to run both games using default settings and found that it lags so badly and have broken audios when in game but it went smoothly at the title menu . One more thing, whenever I'm idle from Project Diva Extend at the title screen, there's should be like a short opening movie right? But somehow no audio or voice could be heard at the opening movie...most people said that if you enable Attrac3+ you'll heard some voice or BGM but not for me. Thanks for reading and I hope you can help solve my problem. Oh almost forgot heres the specs of my device

Device: Samsung Galaxy Grand Duos (GT-i9082) running on official JB Malaysia firmware.
CPU: ARMv7 Processor rev 0 (v7I)
RAM: 823112kB
GPU: I dont know how to check my GPU info
Android: JB 4.2.2

->Does overclocking your device helps improve game performance? if yes, how? Ok thats all for now thanks in advance