Since ICS Google has decided to link the volume of ringer and notification volume together. This Xposed module can separate the two streams as they were before ICS.

Requirements:
1. Your phone must be rooted
2. Xposed framework must be installed first http://forum.xda-developers.com/showthread.php?t=1574401
** MTK devices are not compatible **

Instructions:
- Install the module
- Run Xposed Installer and enable the module Separate ringer & notification volume link in ICS/JB
- Reboot the phone