Change CM9 default Music App

# adb shell
# su -
# bash
# mount -o rw,remount -t yaffs2 /dev/bloc/mmcblk0p1 /system
# rm -rf /system/app/Music.apk
# cp /sdcard/CM9Music.apk /system/app/Music.apk         
# rm -rf /data/data/com.android.music
# rm -rf /data/data/com.android.musicvis
# reboot
or
# adb root
# adb remount 
# adb shell
# rm /system/app/Music.apk
# cp /sdcard/CM9Music.apk /system/app/Music.apk
# rm -rf /data/data/com.android.music
# rm -rf /data/data/com.android.musicvic
# reboot