Hello Kishore1022,
It sounds like you have a new album downloaded and the tracks all have a very low volume. I recommend checking to see if Sound Check is enabled in the Music settings.
iPad User Guide
http://help.apple.com/ipad/7/#/iPad99f37037
Go to Settings > Music to set options for Music, including:
Sound Check (to normalize the volume level of your audio content)
You can also try downloading the purchases onto a computer, with either of these articles depending on your version of the operating system:
iTunes 11 for Windows: Download previous purchases from the iTunes Store
http://support.apple.com/kb/PH12491
Or
iTunes 11 for Mac: Download previous purchases from the iTunes Store
http://support.apple.com/kb/PH12283
Thank you for using Apple Support Communities.
Cheers,
Sterling
Thank you for using Apple Support Communities.
All the best,
Sterling