Things You'll Need
Instructions
Turn on your PSP and start playing your movie, song or game. Boost the volume of the PSP by pressing the volume control buttons located on the button bar, which is below the screen. The (+) button will turn the volume up, and the (-) button will turn the volume down.
Plug your PSP into a larger speaker if the volume still is not high enough. You need an auxiliary cable with two male ends to plug the PSP into a speaker. You can use a three-foot cable. Plug one end of the cable into the PSP and the other into the speaker input.
Plug any FM transmitter into the PSP headphone jack and tune your radio to the FM station on the FM transmitter. Your audio from the PSP will now be playing through the radio speakers in your car or home. This will allow you increase the volume greatly.