Hacking Using CMA to transfer MP3s on PSTV with USB as ux0?

[squall23]

I know the title is a little confusing but that's the simplist explanation of what I want to do.

I have a PSTV on 3.60 henkaku, and I'm using a USB drive as my ux0. I tried transferring some MP3s through CMA but it keeps giving me an error.

Does anybody have an ideas?