how do i fix the audio on my PSP?

Answer 1

What Do You Mean By Audio?
Are The Speakers Not Working? Headphones? In-Game?

If You're Playing A Game, Check With The Game's Audio Settings If That's The Problem..

If It's Your Headphones, Try Another Headphone To See If It's Better Or Not..

As For The PSP's Speakers, Maybe You Should Contact Sony (1) And Tell Them What The Problem Is..
If There's Something Really Wrong With Your PSP, They Should Help You Out And Fix/Replace It..

Hope To Help, And If You Have Any Additional Questions For Me, Don't Hesitate To Contact Me!