Mobile App doesn't pause music on incoming call

[TBNolan]

When I am using Spotify on my mobile and an incomming call comes in, the music doesn't pause and I often miss the call if I'm listening in the car.

Other details:

-Android 4.0, Droid Razr Maxx

-this ONLY happens when my phone is set to vibrate. If the ringtone is on, it behaves as it used to-- pausing the music as the call comes in and resuming on ending the call

Is this a bug or a feature?

[Stahl123]

I seem to have the same issue with android 2.3.6. Any solutions?