iPhone 4 iPod progress bar lost

Progress bar? Like for the song?

Tap on the album picture when you are playing a song. It will pop up.

 

Hello everyone!
I have an iPhone 4 16gb!
iOS 4.2.1, Jailbroken!
I've downloaded many songs frOm YouTube Downloader and added thEm to the IPod.app!
Everything was working fine until today!
I tried backing up the downloaded videos through iPhone Browser! Out of 47, it backed up only 7 and said something like, "the iPhone source is bad or something!"
After that I opened the iPod.app on my iPhone but it would never open! Always crashes! I tried resyncing, rebooting, respring, even tried removing YouTube Downloader but still the IPod.app won't open!
It opened 2-3 times but it would only show the downloaded videos!
No podcast or song!
So, my real problem is, my iPod.app won't open! Even if it does, it only shows the downloaded videos but not the songs and podcasts!
Plz, tell me a solution to this without restoring my IPhone!