Cannot silence ringtones and notifications when a headset is plugged into my device

I have a very annoying problem. When I'm listening to music, podcasts etc. or anything with my head phones,and my device is set to either silent or vibrate when a notification or phone call comes through it blares through to my headphones especially phone calls. I use Viper to enhance my audio and listen to my music at a high fidelity and when a phone call comes in it is extremely loud through my headset. I'm running a ported rom Uncarrier V2. If anyone has any suggestions or a possible solution it would be greatly appreciated :).
Thanks in advance!!