I'm a SVC+ user myself as well. It's superior compared to all the other volume control applications out there for sure. I'm especially happy with how less battery it uses as battery has always been a concern for me.
Try Smart Volume Control+. I've been using it for a week now and I am really satisfied with it. I was looking for the same thing you are looking for and I finally stumbled upon an application that does the job after a long day's search.
They have a website which contains more information here...
You should post the specs of your phone. It's impossible to make a blind comment about this. I'll try to help you out once you reply with the information I need.
You should be able to update by downloading the FW somewhere else though if anything. Just food for thought.
Google Play needs to recognize that you have the application in your device, else you won't be able to post. If you have the application already, try a reinstall!