Tips On Increasing Emulator Framerate???

I have tries a few emulators but morphgear is by far the best, but seems like the GBA games no matter where i try i cant get a playable framerate, really slow.... SNES, NES, and GameBoy Color are practically perfect even with sound on but i cant seem to get similar results for GameBoy Advance.Is there any tips on increasing performance in frames or tweaks i can do to make my device faster from any fellow emulator users? Or is the Vogue chipset too weak??