Newly added music problem

[rzld]

I have a problem in the "newly added" playlist in Walkman. Whenever I open the newly added playlist after my phone is plugged in to my computer, the playlist shows older songs instead of the latest songs copied to my SD card.

Anyway, I am using Xperia SP. But this problem also occured on my Xperia Go with Jelly Bean update, so I think it's the software problem. Can anybody here give me the solution? I have tried to clear the data of the Walkman app but that doesn't help. Thanks.

[Alexander1]

How are you transferring your music to your phone? Are you using any program or do you simply copy and paste the files through the file explorer? Do you experience the same behavior if you move the music to the internal storage?

[rzld]

I'm trasnferring it via USB with mass storage mode, so I copied it with Windows Explorer. I haven't tried moving the music to the internal storage, but I think it only happened with SD card because the pre-added music never appears in the playlist.